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aka: Daily Life With Monster Girl

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The protagonist isn't in the picture, but we all know you're just here for the monster girls anyway. note 

Monster Musume (known in Japan as Monster Musume no Iru Nichijō, meaning "Everyday Life with Monster Girls") is a manga written and illustrated by Pixiv artist Takemaru "Okayado" Inui, which began serialization in Monthly Comic Ryu in 2012. It tells the story of ordinary student Kimihito Kurusu and the monster girls he is hosting, a lamia named Miia, a harpy named Papi, a centaur named Centorea (a.k.a. Cerea), a slime girl named Suu, a mermaid named Meroune (a.k.a. Mero), an arachne named Rachnera, and a dullahan named Lala.

Three years ago, the government revealed the existence of monsters to the world and began working to integrate the two societies. Just like human cultural exchange programs, some humans have been sent to live with monsters, while some monsters are now living with humans. Due to an error, Miia ended up at Kimihito's house by mistake, but her case worker is too lazy to fix it. Over time, Miia ended up falling for Kimihito, but due to the laws governing the cultural exchange program, if they ever consummate their relationship, she'll be sent back to her own country.

Things get even more complicated when the other girls arrive...

This series has a wiki.

The manga is licensed in English by Seven Seas Entertainment, along with the official manga anthology Monster Musume: I ♥ Monster Girls. It also has an anime adaptation which aired in the Summer 2015 anime season, titled Everyday Life with Monster Girls, and has been licensed to Sentai Filmworks. See the preview here. Crunchyroll is also streaming the anime, which can be viewed here for folks in the following regions: note 

In December 2015, DMM launched a free-to-play browser game with a similar style to KanColle and some Ren Ai elements under the title Daily Life With Monster Girl Online. Sadly, it was announced that the game would be shutting down on November 22, 2016.

An OVA was released in November 2016, featuring an extended anime adaptation of Chapter 17 of the manga. A second OVA was released in April 2017, featuring an anime adaptation of Chapter 26.

This manga is based on the author's previous online hentai manga shorts, Living with Monster Girl; for the sake of keeping this page as clean as Monster Musume can be, please do not post tropes applying to that one.

For Okayado's other works with monster girls, see Deadline Summoner and 12 Beast.


Monster Musume provides examples of:

    open/close all folders 

    Tropes # to D 
  • 2D Visuals, 3D Effects: The kissing fish in Episode 9 feel out of place among the other sea creatures.
  • Aborted Arc:
    • The whole "can't have sex with a homestay" law seems to have just been completely forgotten in later chapters, where there are amorous dating meet ups being set up without any commentary as well as several inter species couples out in the open, many of which are openly sexual. Albeit there are implications that the government has simply given up trying to enforce most such rules (especially with groups like Black Lily competing with them in the PR department), instead merely trying to make sure any actual sex takes place in private and that no one gets abused. For Kimihito this means that the only thing really stopping him from going all the way with his housemates is his uncertainty/not wanting to hurt them, and their own competitiveness with each other making it difficult for any of them to make a move.
    • One of the earlier Arcs was around Kimihito being the first to get married to one of the girls to bridge relationships between monster girls and humans, only for later chapters to casually show several human and monsters as fiancees or already married.
  • Accidental Marriage: Centaurs have strict rules about only letting one's "master" ride on their backs. Naturally, Kimihito finds this out right after he spends most of chapter 4 riding Centorea.
  • Action Girl: The special ops, with special mention to Zombina who totes uzis.
  • A-Cup Angst:
    • Manako's response to finding out that a 103cm I-cup bra was insufficient to contain Centorea is to go into shock and grab at the air in front of her chest. Even the fairly buxom Miia and Rachnee are slightly alarmed.
    • Tionishia tries to cheer her up by saying small breasts aren't bad. Doppel points out Tio can't understand what it means to be flat since her own bust is 160cm, which is big enough to make Centorea seem flat by comparison.
    • Centorea herself, believe it or not, suffers from this slightly when she meets Cathyl, a minotaur who she is displeased to note is bustier than her. Though it should be noted that Tionishia is also bustier than Centorea, but she's never had a problem with hernote .
    • A (relatively) short minotaur named Cream is self conscious about her bust, being only a J-cup. Kimihito points out that minotaurs have a different standard for bust sizes. While she's huge by human standards, for a minotaur she is quite underdeveloped.
    • It is worthwhile to mention Papi, Shiishii the Jiangshi and Alusia the lightweight centaur. None of them indicate actual angst but they are among the few characters who have speaking parts and don't have the astounding proportions common in the manga.
  • Adaptation Expansion: In both the anime and the manga, there's a scene shortly after Rachnera's introduction, where Centorea runs off with Kimihito, and they get surrounded and accosted by a gang of racists who make a bunch of disparaging and sexual remarks about Centorea, which she ignores, but then a slight against Kimihito sends her into a blind rage. In the manga, this is just a childish slight against him, speculating he has a tiny penis, but in the anime, the crowd mockingly questions how Kimihito could think any human could possibly be well endowed enough to satisfy a centaur woman, who'd need someone literally hung like a horse. This makes her blind rage far more believable in light of the later manga subplot of how utterly screwed-up Centaur mating is, and how mating for love is heavily looked down upon in favor of marrying males for their size and strength, something which she refuses to do.
  • Adaptation-Induced Plot Hole:
    • In the manga, Cerea drags Miia along so they can search for Lala's head, while the anime has Miia frantically volunteer herself just to not be left with the headless body. Both versions display that she's much more terrified of the head (even just knowing that there's one lying around), so she should have believed that staying with the body was the lesser of two evils, though it is hinted that it's the absence of Kimihito when something scary is happening that she's most afraid of.
    • In the anime, the episode that has Kimihito help Miia with her shedding takes place after Suu and Mero have joined the household, whereas in the manga, the chapter took place beforehand. This creates the plothole of Suu being badly affected by Miia's cooking despite it being shown in episode 12 that she can eat poisonous plants just fine (albeit becoming poisonous herself). note 
    • In the anime, the episode that has Kimihito catching a cold happens after Rachnera has joined the harem, instead of before like the manga. This gets lampshaded when she finally tires of the squabbling of the other girls and webs them all up, only to have Suu run off to "help" Kimihito before she can deliver any instructions of her own.
  • Adaptational Modesty: Let's put it blandly: the single page comics that started it all were barely even Porn with Plotnote . The anime falls into the ecchi category (albeit pretty heavy ecchi). That said, over time quite a few background characters do end up blurring the line even further, with censored depictions of sex and even massive orgies.
  • All Men Are Perverts: Not even Kimihito is above this. He may have superhuman self-control, but we get numerous looks at his internal monologue as the girls try to charm him and they show that he does, in fact, have a working pair down there.
  • All Myths Are True: All monsters, at the very least.
  • All There in the Manual: The MonMusu Collection end-cards in the anime, which give detailed facts about different extra-species:
    • The first expands on lamia as well as their sub-species, like echidna (which have venom like vipers) and melusine (a winged type).
    • The second shows harpies and their sub-species, including raptors (carnivores that are more like eagles or hawks) and poultry (which are essentially chickens in harpy form).
    • The third covers centaurs and their sub-species, which include lightweights (aka racing centaurs, a fragile type built for speed), heavyweights (built for size and strength), and dairy types (with minotaur-sized breasts and prodigious milk output).
    • The fourth looks at slimes and their sub-species, such as red slimes (an acidic type with the personality to match) and green slimes (a poisonous type who can't keep full humanoid form).
    • The fifth is about mermaids and their sub-species, among them sharks (who have a skeleton made of cartilage in their lower bodies) and fresh water class (who travel between rivers and oceans like salmon).
    • The sixth looks at arachne and their sub-species, like small breeds (which are small and good at jumping like jumping spiders) and large breeds (which are larger and covered with hair like tarantulas).
    • The seventh explains Monoeyes and their sub-species, like the Cyclops (who are larger than the others) and the Backbeards (who have a variety of eye powers like hypnosis and Eye Beams).
    • The eighth covers zombies and their variants, such as Mummies (who often have difficult personalities due to being former royalty) and Chinese Vampires (jiangshi; who practice tai chi to ward off joint stiffness).
    • The ninth discusses ogres and their relatives, such as trolls, which are bigger and more muscular than regular ogres; and gigantes, which are even bigger and stand more than 10 meters high.
    • The tenth discusses dragonewts and their relatives, such as Ryu-jin, which are a wingless Eastern-dragon species, and wyverns, which have their wings on their arms and can actually fly with them. The card also has doppelgangers, who have no sub-species mentioned.
    • The eleventh covers dryads and their relatives, such as alraune, who are flower-based, and mandragora, who are a root-based species known for their extremely loud screams. The card also has dullahans, who have no sub-species mentioned.
    • The twelfth is about the various long-lived and slightly out-of-fashion subspecies of devils, such as greater devils, who look like Kogals from the 90s, and elder devils, who look like disco dancers from Japan's bubble economy in the late 80s. The card also has kobolds, who have no subspecies mentioned.
    • The manga also has pages after the story is done devoted to explaining the physical traits and societies of different monster girl types: for example, kobolds have a near-monopoly on the world's cobalt supply, making them all extremely wealthy. This is why Polt is able to afford to build her massive gym and stadium.
  • All Women Are Lustful: The Series, God dang it. Those who are not in for outright sex will tease the protagonist to no end. Chapter 31 shows that they're all genuinely oblivious to the idea that most girls wouldn't like mixed baths. Lamia in particular are known for this In-Universe, while Satyrs take it up to eleven. Chapter 64 shows all of the women being the aggressive ones in the mixed baths, to the point the Main Characters were hired to stop any sex from happening, something that exhausts them very quickly. The ways in which monster girls display it varies substantially, and most of the time most can control themselves just fine if they want to (and many are noted for loyalty if they find someone to love), but a quite high libido is presented as a generally unifying trait for them.
  • Amusing Injuries
    • In chapter 5, Kimihito walks into the kitchen, and has a big u-shaped hoofprint on his face. He explains to Miia that he accidentally walked in on Centorea while she was bathing after her morning exercise. Later Miia has hoofprints all over her as well when she tries to stop Centorea from running away, with Kimihito, from filling out her [Centorea's] homestay application. Then there are all the times Kimihito gets crushed by doors...
    • Zombina as well, since already being dead she can survive them. She takes her hand falling off as one would their wrist watch coming loose.
  • Animation Bump
    • The anime already had good animation, but the twelfth episode pulled out all the stops, featuring many fluid and elaborate animations.
    • The animators included an amusing reference to this, with Kimihito destroying the infamous QUALITY Cabbage (which became a symbol of cheap animation) during his "food rampage" at the end, as to signify that they are against cutting corners and half-assing things.
  • Ape Shall Never Kill Ape: Inverted since only non-humans hurting humans and vice versa is explicitly forbidden under the Foreign Exchange Bill.
  • Arbitrary Skepticism: Despite being extra-species themselves, the girls have a hard time believing that dullahans are anything other than an old myth, even after Lala turns up. Kimihito lampshades this by saying something like "You guys are in no position to talk.".
  • Aren't You Going to Ravish Me?:
    • Most of the various girls that move in with Kimihito really want to have sex with him. But due to a combination of him being Above the Influence, and also being thrown in jail if he did do it with them, he never takes advantage of them, even when they practically throw themselves on top of him.
    • There have actually been several occasions where sex would have likely occurred (Kimihito even noting his resistance to his sexy roommates has its limits), only for an Amusing Injury or Interrupted Intimacy to occur. The chances of a successful seduction get lower as more monster girls start living with him, because while most of the girls would jump at the chance for a romp in the sheets (or on the floor, or anywhere really) with Kimihito, they, similarly, will stop at nothing to keep the OTHER girls from getting intimate with him. Miia and Cerea in particular are prone to protecting his "purity" (for themselves, that is).
    • Even Kimihito becomes guilty of this by the end of the farm arc, after the satyrs end up seducing every other extraspecies girl on the farm, resulting in the minotaur and faun girls no longer needing Kimihito for milking or sex (though they do later start missing him as his technique was just that good).
  • Art Shift:
    • In episode 3 of the anime Miia, Papi, and Centorea are about to fight each other for Kimihito's affections. They are rendered as creepy, Madoka-esque blobs of color with no pupils, moving in an unnatural way. The scene also ends in a Pastel-Chalked Freeze Frame.
    • In chapter 70, a pack of mohawk-sporting biker bandits trying to rob the farm are drawn in the style of Fist of the North Star.
  • Artistic License – Biology: All over the place. Then again, monster people were considered fictional to humans until a while ago. There might be an explanation for how their bodies work in their world, though they wouldn't necessarily work in the real world. Likely justified due to supernatural elements; after all, it's not as if Zombina or Lala could even be "alive" otherwise.
  • Attacking Through Yourself: Zombina, being restrained from behind by an orc, fires her guns through herself to hit the orc.
  • Audience Participation: At first the author added in new Cute Monster Girls to Kimihito's harem based on the readers' votes, but once the harem (both main and auxilery) got rather big, he switched over to Official Fan-Submitted Content, with him adding background humans and monster girls based on the fans and their OCs who gave him images and details about them.
  • Author Appeal:
  • Author Avatar: In a bonus chapter for chapter 8, the author is portrayed as a hermit crab. He even gets a cameo as a plushie in some panels.
  • Awesome, but Impractical: Manako has a transforming Briefcase Blaster. However the bonus chapters at the end explain that it's riddled with so many flaws that only a few prototypes were produced before the project was scrapped.
  • Balanced Harem: All the monster girls have their equal take of Ship Tease with Kimihito. Kimihito freely admits to himself that he'd enjoy being married to any of them. The girls of MON have all kinda-sorta fallen in love with Kimihito as well, though they'll just have to get in line behind the main seven.
  • Balloon Belly:
    • In chapter 57, while the girls are enjoying a spa day, Papi gorges herself so much that this trope is basically taken literally.
    • In chapter 59, Miia, Centorea, and Mero all get one by the time their mini vacation comes to an end, while has Papi DOUBLED in size.
  • Barbie Doll Anatomy: The broadcast version of the anime does a good job of not drawing too much attention that it's somewhat censored, unlike the manga, but this trope is particularly glaring when Kimihito goes on a fake "date" with Zombina; she unstitches her breast, causing it to flop onto the floor. Kimihito freaks out a bit when he picks it up and realizes what it is, but what's shown is a perfectly round, smooth, flesh-colored lump.
  • Batman Gambit: The threat of "D" was thought up in order to make Kimihito closer to one of his girls so he can choose one. Unfortunately for Doppel, the plan's originator, the whole thing completely backfires. Instead of picking a single girl, he got closer to all of the girls living with him, and may have even captured the affections of her co-workers too.
  • Beauty Equals Goodness: Played straight at first, but then enough exceptions showed up to the point this trope is basically averted:
    • At first, the biggest jerkasses of the manga are the racist couple, the director, and the orc gang. None of them are pleasant to look at.
    • Averted by Rachnera's initial host family. They look like fairly normal, decent people, but they sold her off because she wasn't what they were expecting...at least according to Rachnera. Chapter 26 reveals that while they were off-put and intimidated by her, they gave her a fair chance until Rachnera accidentally cut the daughter's face with her claws when she slipped and fell off a ladder. It seemed this was the deciding factor into their belief that they truly could not live together.
    • Also averted pretty hard by Draco, and even harder by Mero's mom. Miia's mom is also fairly nasty, being sufficiently cold-blooded (forgive the pun but it fits) to use her own daughter in a political play.
    • Apparently played straight by Killa the Killer Bee. She's the most serious and least attractive villain introduced so far. She instantly tries to kill Kimihito with her stinger and has a nightmarish insectoid face and arms that are covered in a carapace that makes them look sinisterly skeletal. Subverted in chapter 45, when it's revealed that she really wasn't trying to kill Kimihito and her venom isn't actually that strong - she just has a one-sided feud with Rachnera, who humiliated her by catching her in a web. When she was trying to cross into Japan, she saw Rachnee and began hurling threats at her, resulting in getting herself classified as a dangerous species. Once she's calmed down, she's also drawn in a much more human-looking and attractive manner, with a more human-looking face and more emphasis placed on her breasts and hips than her stinger and inhuman hands and feet.
    • Subverted by the Echidna's grotesquely muscular communal husband: despite his daunting appearance, the guy is an absolute sweetheart to the tribe, hand-crafting them jewelry that they adore, and coming across as a perfectly friendly guy overall.
    • Averted yet again by Meamil: she's a gorgeous, maternal perverted lunatic.
  • Bedmate Reveal: The very first scene of the series: Kimihito wakes up to find that Miia is in bed with him, having decided to use him as a warm body to warm herself up. Unfortunately, that also means her instinctive reaction to someone trying to wriggle free is to grasp him tightly in her coils. At first, this only means a Marshmallow Hell, but Kimihito quickly faces the prospect of being crushed to death. In chapter 58 he wakes up with Saane in his bed intending to initiate sex.
  • Bee Afraid: Chapter 44 introduces the first of the three extraspecies girls that came illegally to Japan, Killa the killer bee. She is based on the very dangerous ōsuzumebachi (Japanese Giant Hornet), is treated almost without a trace of comedy, and wastes no time in going after Kimihito with her seemingly deadly sting. That is until the much tamer truth about her comes out.
  • Bifauxnen: Draco turns out to be one
  • Bigger on the Inside: Kimihito's house has enough space for every extra-species girl he lives with, including an Olympic-sized pool for Mero, a bath big enough for Miia's snake body, and rooms comfortable for both Cerea and Rachnera; and while it has explicitly been remodeled and added to, the house is never referred to as anything resembling palatial or a mansion.
  • Big Sister Instinct: Surprisingly enough it's Papi who shows the most protectiveness towards Suu.
  • Bizarre Sexual Dimorphism
    • Downplayed with centaurs; due to being a combination of Barbarian Tribe and Hordes from the East for much of their history, only the strongest male centaurs survived long enough to breed. This "natural selection" caused the next generation of male centaurs to become more muscular, more violent, and (unintentionally) more ugly. However, in today's modern world, the war-specialized muscular brutes that are the male centaurs have fallen out of use, and female centaurs are looking elsewhere to find a mate.
    • Orcs as well. The male orcs shown in the manga and anime look like anthropomorphized pig men, while the browser game features a much more comely female orc.
    • Chapter 49 shows some mummy men that look like goofy little men covered from head to toe in bandages; the mummy girl shown later is a sexy brown-skinned lady with a few bandages in strategic places, much like the ones in the online game and the subspecies cards in the anime.
  • Bland-Name Product: There are some monster puns for certain products like Monsterbooks Coffee and Duel Monmusus.
  • Bloodless Carnage: In chapter 39, Zombina gets torn in half by a Jiang-Shi Friendly Enemy of hers, and there's absolutely no blood, guts or gore around. Of course, the manga is primarily a light-hearted comedy; however, in Zombina's introductory chapter, she was shot multiple times and bled profusely. Though given that she was disguised as a regular police officer then and was deliberately setting herself up to get shot and "killed," she was probably using blood packs in that instance.
  • A Bloody Mess: In chapter 6, Kimihito was at the fridge when the girls caught up and rammed into him. In the aftermath they saw him lying on the ground with the splattered ketchup, thinking it was his blood.
  • Bowdlerise: In the digital version, which carried on to the official English release, a scene with Cathyl was censored so that milk is not seen coming directly from the nipples.
  • Breaking the Fourth Wall: The color pages at the start of chapter 39 feature Doppel talking to the readers and showing them the other MON girls in their sleep. Since she's an Eldritch Abomination of sorts, she managed to see beyond the manga pages!
  • Breast Expansion: As part of Suu's shape changing abilities, if she consumes enough water she can change from the appearance of a young girl to a buxom adult.
  • Broke Episode: In chapter 25, Kimihito finds out he doesn't have a lot of money leftover due to having to buy so much food to feed the girls with, and they're out of food. Fortunately the vendors give them a lot of free food, mostly stuff they couldn't sell, and later Suu and Kimihito visit Kii, who gives them a lot of edible plants from the forest. Ms. Smith later tells him that the government would reimburse him for living expenses. He tells her she should have told him about this sooner. He then spends almost all of Chapter 26 Out of Focus, having his various receipts and claims audited by the government. .
  • Brutal Honesty:
    • Rachnera generally does this as she doesn't like sugar-coating things. She's happy when Centorea says she dislikes her, after pretending she didn't because it means she finally spoke her mind. Or when she tells Centorea her sandwiches are not very good because she just put chopped raw vegetables between two pieces of bread.
    • The minotaur Chizu is incredibly blunt and straightforward, leading to an amusingly embarrassing moment when Kimihito's milking her and she narrates in minute detail how good it's making her feel.
    • When it comes to talking about carnal matters, it seems satyrs as a whole aren't big on the whole 'tact' thing.
  • Bullying a Dragon:
    • After being offered help by Rachnera, the Director tells her that she has no right to be high and mighty when he's the one who can make money off of her webbing, and that she should keep it in one place, not all over the building. She proceeds to encase him in webbing.
    • Later, Rachnera is taunted by Lilith, in an attempt to break her. See Shut Up, Hannibal!.
    • The leader of the orcs chases after Doppel, who was in the form of Lilith, with the intent of raping her. Kimihito distracts him before he can do so, and Doppel gets her revenge by transforming into a monstrous form and terrifying the orc into insanity.
  • The Bus Came Back: Miss Octo, who is originally part of Meroune's arc back to her home, pops up in chapter 66 as a couple counsoler in Yukio's inn and bathhouse.
  • Butt-Monkey: Kimihito suffers abuse on a daily basis from the girls (mostly unintentional). Draco becomes this after her first appearance.
  • Call-Back:
    • In Chapter 26 in Cerea's room you can see the body armor and the saddle she has used in previous chapters.
    • The chapter featuring Doppel has her turning into various girls, including a member of ANM48, who weren't seen at all since chapter one.
    • Chapter 59 calls way back to chapter 6, including flashback images from that chapter, when Kimihito is reminded about the effects the full moon has on extraspecies persons.
  • Canon Immigrant: At the beginning of Chapter 43 Miia is reading a fashion magazine for liminal girls. The featured models come from the online game, Daily Life With Monster Girl Online. (To be more specific they are Kalolo, Bisque, Rus and Rohe)
  • Can't Have Sex, Ever: Not without the monster girl being kicked out of the country, anyway. Note that real-life exchange programs usually have this policy. Subverted as of chapter 5, as Kimihito has been made into the guinea pig of a new amendment to the exchange program allowing interspecies marriages, presumably rendering the rule invalid. As the series progresses we see many other men and monster girls getting into clearly romantic relationships without a word about the no sex policy.
  • Cast Herd: The Dairy Arc and the Lamia Arc had huge numbers of new characters, but the Dairy Arc takes the prize. Most of the dairy workers remained in the background, with no dialogue, but Volume 14 has an omake in which all forty girls (20 minotaurs, 10 pans, 10 satyrs) are given names, measurements, capsule descriptions, and portraits with distinct appearances. This is a stunning amount of work for disposable background characters.
  • Casual Danger Dialogue: Happens from time to time, due to the often dangerous situations Kimihito is put in by the monster girls.
  • Carnivore Confusion: People keep assuming liminals have these kinds of issues, like that harpies won't eat poultry or mermaids won't eat fish. They don't, and find the assumptions ridiculous; after all, humans eat other mammals, don't they?
  • Chekhov's Gun:
    • When Miia first meets Draco, Draco gives her a can of coffee as a gift. After Kimihito saves her from Draco, she throws it at Draco to shut her up.
    • When Mero is introduced, there are times when she speaks with a high regal tone, with her being portrayed as a regal monarch. Turns out, she is a princess for real.
  • Chekhov's Skill: Kimihito's living with and being able to befriend a long list of various non-human ladies help his progress in the Lamia tournament to decide leadership of their people as Miia's Tribe's champion.
    • Against the Echidna Tribe, Kimihito is quick to notice the jewelry the ladies seducing him wear and compliment it, getting past their rough outsides and drawing out their softer sides.
    • Against both the Melusine Tribe and Echidna Tribe, he uses his knowledge of Miia's tail being sensitive to erotic pleasures and his breast massaging techniques to help seduce them. Against the former, these doesn't work that well as the Melusine are even more hyped for sex than other tribes.
    • His resistance against and disinterest in the overly lewd situations when too many women start fondling him allows him to not get an erection when faced with the hyper-sexual Melusine tribe.
  • Classical Mythology: A lot of the girls are based on Greek myths: Miia (lamia), Papi (harpy), Centorea (centaur), Rachnera (arachne), Manako (cyclops), Kii (dryad), Cathyl (minotaur), Merino (faun), Ton & Kot (barometz).
  • Color-Coded for Your Convenience: The main girls have consistently followed a color scheme with their hair, feathers, scales and the like, and is utilized in the anime opening.
    • Miia: Red
    • Papi: Blue
    • Centorea: Yellow
    • Suu: Green
    • Meroune: Pink
    • Rachnera: Light Purple
    • Lala: White/Grey
    • Additionally, Smith: Black
  • Color Failure: Manako after hearing just how much larger Centorea's breasts are than her own.
  • Collective Death Glare: In episode 6, four of the monster girls find themselves as interview subjects for a documentary being made by a strange director. Kimihito had reservations about the director at first but ultimately went along with the plan. Over the course of the episode, the girls get caught in progressively more compromising situations, until they finally discover that the director intended all along to sell the "documentary footage" as monster girl porn. The girls are less than pleased, and they all shoot collective daggers at the director.
  • Combat Commentator: Parodied by Miia and Centorea during Suu's Kaiju fight with the Colossal Slime.
  • Company Town: The Black Lily organization is a more-luxurious smaller-scale version of this. It's president, The Broker, insists that it's profitable enough for all parties involved to benefit, but the implications of this trope are a major source of menace for the organization.
  • Continuity Cameo: Polt the Kobold, who has a much more prominent role in the manga, is shown running through the park in episode 10 of the anime.
  • Contrived Coincidence:
    • The entire "D" plotline revolves around someone sending threatening letters to Kimihito, known only as "D". On the three subsequent attempts to find the culprit, three troublemaking monster girls are encountered whose species names all start with D note  but aren't the actual "D" (really Doppel). Right after the real "D" is revealed, another "D" with similar motives pops up with no connection to the previous "D," with the culprit again being a monster girl whose species name starts with D (Lala the dullahan).
    • Subverted. When the main characters are trying to root out a vampire (which is a very real and very dangerous extra-species) at a monster convention, by an amazing coincidence there's a huge display of vampires' classic weaknesses that they conveniently use to test on the person they think is a vampire. But while at first it seems to serve no purpose other than to comically conveniently further the plot, some other monster girls explain that it's there so that the countless other blood-sucking monster breeds (who aren't nearly as dangerous as vampires) can easily demonstrate to the people they meet at the con that, despite sucking blood, they aren't vampires.
  • "Could Have Avoided This!" Plot: If Kimihito had mentioned his financial troubles in feeding the household to Ms. Smith (or alternately, if she had remembered to tell him about the government reimbursing him for such in the first place, rather than at the end of the chapter after eating all his food), Chapter 25 wouldn't have happened. Kimihito is left even more frustrated when he realizes this at the end, and the gang end up eating out all day the next day... and getting thrown out of a steakhouse.
  • The Coup: Played for laughs at the end of the farm arc. The satyrs watched as in exchange for milking by hand, the minotaurs and fauns did more work. So, they studied Kimihito's technique for milking the breasts by hand. On the eve of his departure, when a majority of the other ladies on the farm were pressuring him to stay, urged on by the effects of the full moon, the satyrs arrived on scene to save Kimihito by proving to have become adept at milking the other ladies. This turns the ladies who were focused on keeping Kimihito into eagerly accepting the touch of the satyrs. The satyrs, for their part, don't have to do chores, get to touch breasts as much as they want, and get paid for it. A major win and they control the farm now. That said, it's later noted their position is far from stable, with the other girls all quite willing to switch back to Kimihito should he ever become available to them as they regard his technique as still superior.
  • Crack Defeat: In chapter 17, Miia and Meroune have a swimming race. Mero is expected to have the advantage, being a mermaid, but Miia uses her 8-meter body to simply stretch a long distance, allowing her to cover much of the pool without swimming. In the end, both of their Logical Weaknesses come into effect (to clarify, the heated pool isn't warm enough to keep Miia going and the chlorinated water poisons Mero), and Cerea wins despite not being shown for the entire race. Doubles as a Brick Joke, as Cerea actually does mention that she's going to participate in an earlier panel, but she's ignored despite her protests.
  • Crapsaccharine World: The first chapter lays out a pretty optimistic view of the world, but also lays out subtle indications that things are not quite as happy as they seem. The exchange program's been a "huge success", various extraspecies have been able to integrate well with human society, and it didn't really change the world much. However, the exchange laws are explicitly noted to be full of loopholes:
    • While either humans or extraspecies harming each other would punish one side or the other, this simply leads to people from both sides abusing the law to their own advantages while also being protected because they haven't technically harmed someone, and the legally permitted penalties are so absurdly negligible that the orc leader points out that all he'd get for what amounts to a terrorist attack is community service.
    • If an extraspecies is found away from their host, they are the one in violation of the laws, even if the reason for it is something like being sold off to someone else, with no mention of any penalties to the host for the separation. Heck, in Chapter 26 it is even revealed that the host family that sold them off can still be a host family for an extraspecies, even to said extraspecies they sold off.
    • Young monster girls are also in danger of being kidnapped by humans, likely to be sold into any number of horrifying scenarios. The ones rescued in Chapter 20 are children.
    • While extraspecies along the lines of cat girls have integrated well, to the point of being celebrities in some cases, the "various" successes do not apparently include the more monstrous variants, such as most of the girls living with Kimihito. Racism toward them is shown repeatedly throughout the series.
    • It's noted that most places are not built with non-humanoids in mind. Chapter 15 implies that Kimihito's home is one of the only places that is. Justified because the other species were unknown to most of humanity until recently; it takes time to make full-scale adjustments like that. In chapter 17 it was shown that attempts at integration are being made, but it's still a road with speed-bumps, since there are lots of different species and each has different needs. The equipment in the gym that was set up for extra-species, for example, was full of human equipment unsuitable for those without humanoid legs.
    • The chapter introducing Miia's mom has introduced a bright spot in this darkness. In The Unmasqued World, the lamia can procreate with much more ease, since with access to human society, they can also have access to human sperm banks and can procreate by artificial insemination. Note though this option is never mentioned, perhaps because lamia prefer actually mating with a man, pleasure seeming to be their aim as much as procreation.
    • Chapter 36 has put a dark twist to the mermaid society. Because of their love of tragic love stories, many mermaids have eloped with humans. Because of this, the overall human-mermaid relationship is a bit fragile. Chapter 37 reveals the elopement problem isn't nearly as bad as it seems. Meroune's mother having exaggerated the scope of it as part of her plan to create tragedy.
    • There's also the issue of if a host has any type of sex with their hosted nonhuman, even if the nonhuman started it, whether or not it was voluntary, they'll be sent to jail, while the nonhuman in question will only get deported. Albeit the government seems to have given up on the "no sex" rule as the series has progressed.
    • Humans don't have it exactly easy, either. For starters, almost all the girls are way stronger than normal people (though many have various weaknesses humans don't). The sea is home to a kingdom led by an extremely rich and powerful (not to mention dangerously unstable) queen that can remodel a normal house without anyone noticing, so who knows what will happen if her beloved daughter ever gets in danger? There are sentient moving treefolk that are shown to take drastic measures against pollution (albeit said dryad was not in her right mind at the time). While the only liminal terrorist group shown is pretty goofy, the mere fact they exist is a quite worrying situation. Shapeshifters and creatures outside comprehension are known to exist, so hope they never turn bad (though mitigated by the one we have met admitting she is not much stronger than a human). Finally, apparently there are demonic girls, but not angelic girls (again mitigated by how little they have to do with mythological demons).
  • Crash-Into Hello:
    • How Kimihito first meets Centorea, where they even lampshade it.
    • His meeting with Meroune also goes something like this. Kimihito plucks her from her runaway wheelchair and ends up smashed between her and a pole during their first encounter.
  • Crazy-Prepared: Yukio's onsen has something for just about every type of extraspecies. They have extra-long pools so Miia can really stretch out, extra-deep pools so Centorea can completely submerge herself, and shallow waterfall pools so Suu can still enjoy the water without being diluted. Yukio herself typically wears a huge sealed full-body suit when walking around the hot springs area, to protect her ice-cold body from the ambient high heat.
  • Creator Cameo:
    • A variation: Okayado's Author Avatar, a hermit crab with pen tips for claws so he can draw, appears in several panels of the manga, and makes multiple appearances throughout the anime.
    • Okayado himself appears in Episode 7 of the anime as someone named Okayada. However, not only is his character not seen, he's barely audible due to other characters talking over him.
  • Cute Monster Girl: It's in the name, folks.
  • Cyclops: Manako was initially called a cyclops, but was later reclassified as a monoeye in the anime. Episode 7's MonMusu Collection shows the monoeye's sub-species, such as the cyclops, who are bigger, bustier, and expert blacksmiths, making them the envy of other monoeyes; the one-eyed monks note , who are actually regular monoeyes that have converted to Buddhism, and are stern both with themselves and others; and the backbeards, who look like children and have an assortment of eye powers like hypnosis, inflicting blindness, and Eye Beams.
  • Damned by Faint Praise: Centorea is shocked when Ren says that her room smells like a barn. When she asks Miia for confirmation, she simply says that she's gotten used to it.
  • Dark Horse Victory: Miia challenges Meroune to a swimming competition in Polt's gym. They are able to go head-to-head, at least until Miia starts to feel ill because of the cold, and Mero almost faints because of the chlorinated water. The winner is... Centorea, who until that moment hadn't even been seen in the panels!
  • Date Peepers: Chapter 18 has the girls tail Kimihito and Ms. Smith, spying on their date together. Turns out it's a cover to flush out an assassin out for Kimihito's life should he marry a monster girl.
  • A Day in the Limelight:
    • Chapters 38 through 42 are dedicated each to a different girl, in order: Lala, Zombina, Doppel, Tionisha and Manako. Lala's chapter sets up the following by making it so MON gets a forced vacation and Kimihito has to go on a date with each one of the girls.
    • Chapter 59.1 follows the daily lives of Curie and her new housemates, the blood-sucking girls from the dating event in chapter 49: Leechi, the leech girl, Moskii, the mosquito girl, and Yatsume, the lamprey girl.
  • Debut Queue: Each of the girls gets a chapter that introduces them. Including the MON, who are a police force consisting of non-humans who take out non-humans criminals trying to exploit the rule that humans can't touch non-humans.
  • Deconstruction: Of the Cute Monster Girl: rather than taking the fantastic creatures at face value, the comic puts a good deal of time and effort into delving into the complexities of their anatomy and how they would interact with the world around them.
    • Mero the mermaid for instance must avoid chlorinated water, as trying to breathe in it is like inhaling bleach fumes and will make her horribly sick. Miia, being part snake, has an aversion to cold. Manako the cyclops has horrible depth perception, and so on. These usually end in humor but also lead to a couple of tense moments, like the time Miia nearly drowns in a pool when the cold water saps her strength.
    • While Extraspecies have been largely accepted into human society, there is still a clear bias towards more attractive and human looking species. Rachnera having been a victim of this prejudice.
    • The idea of a human getting intimate with a woman who's half animal, with the strength to match, is also examined. The girls regularly hurt Kimihito just because they forget their own strength, and he acknowledges that he'll need a lot of physical training and conditioning to have any chance of surviving the wedding night (albeit this seems to be more an issue for Kimihito's harem in particular than for human/monster couples in general).
    • Anytime a Winged Humanoid shows up, they are either child-sized in order to fly or can only glide due to the Square-Cube Law. Species that are both large and flight capable are extremely uncommon and all flying species (except insect-based one) have their arms replaced with wings to get the most out of their pectoral muscles.
  • D-Cup Distress: Centorea's breasts are so big that they make it hard to hold her lance correctly when jousting. Or find a bra in her size for that matter.
  • Defeat by Modesty: Centorea's jousting match with her mother ends in a draw because they both suffer a Wardrobe Malfunction.
  • Department of Redundancy Department: Ms. Smith is surprised at how casually Miia accepts Papi as a second guest, to which Miia responds, in three different ways, that Papi is just a child.note 
  • Depth Deception: In chapter 24, the latest threat to Kimihito's life is a truck barreling down the street. It's shown in extreme closeup for two panels, one of them the standard "Corner of a vehicle speeds into frame before a collision." It's a remote-controlled toy that comes up to his knee. Getting hit by such a thing would be unpleasant, but hardly fatal.
  • Destructo-Nookie: All of the girls during the Lunacy. Kimihito even admits he first has to train his body like mad to even stand a chance of surviving the wedding night with whomever he picks.
  • Didn't Think This Through:
    • Kimihito lies to the Bicycle Cop and pretends to be Papi's host family to keep her from getting in trouble for being in public unescorted. This immediately backfires when he is asked to provide the paperwork to prove it and would have gotten them into even more trouble for lying if Ms. Smith hadn't shown up.
    • Lala visits Kimihito in the hospital alone to avoid all the girls trying to fit in one room or causing a scene. Pretty good thinking until Kimihito realizes a girl with a detachable head, that claims to be the Grim Reaper, might (and does) cause a scene.
  • Diegetic Soundtrack Usage: Some of the web shorts have the girls hum one of their image songs, and one of them has Papi hum the anime's main theme. Doubles as an Early-Bird Cameo, as the image songs weren't revealed until after the shorts were released.
  • "Dinner, Bath, or Sex" Offer: Exaggerated. Miia gives the "food, bath, or me?" offer complete with the Naked Apron to her exchange program host Kimihito (wearing a Salary Man outfit) in one of her Imagine Spots. The response (she imagined) was "I'll have YOU for dinner IN the bath, Miia!", and we get a shot of him doing her on the bathtub still wearing her apron while he's still wearing his Salary Man uniform.
  • Diplomatic Impunity: As the police are not allowed to arrest monsters for fear of a diplomatic incident, a group of Orcs attempt to invoke this in order to hold up a doujin store. Unfortunately for them, there IS a task force meant for just such a situation in the form of MON.
  • Dirty Harriet: In chapter 66, a succubus lifeguard and security worker plays this part in Yukio's inn and onsen. If they get a report of a problematic male customer, she will present herself to be fondled. If the man breaks the rules by doing so, her co-workers will grab him and escort him off the premises and add his name to the blackball list.
  • Dirty Kid: The young boys who usually play with Papi. They like to play games involving water so her thin shirt will reveal her chest.
  • Disability Immunity: Satyrs turn out to be immune to the full moon's normal lust-increasing effects on monster girls because they're so horny the rest of the time that they're used to it.
  • Disproportionate Retribution: Kimihito is at times subjected to this by the monster girls, but usually the injuries he suffers are accidental.
  • Doing in the Scientist: The series initially presented monster girls from a 100% scientific perspective, with focus on how their bodies worked from a biological persepective. As time went on, however, more and more explicitly supernatural elements got added. Doppel-chan was revealed to not just be a shapeshifter but an Eldritch Abomination that's taken on the form of a cute girl for kicks, Lala was revealed to be an actual psychopomp instead of just pretending, and other explicitly supernatural characters like kitsune, ghosts, and baku. The volume 16 omake reveals that monsters are fairly aware of such beings, and while its not a officially recognized name they are often grouped together under the moniker "elite liminals" (or "greater species" in the fan translation), united by them having abilities that science cannot explain. Cerea notes there are a number of types of them, but that as far as number of individuals go they are a rare existence that is not often encountered (the joke being that they don't entirely realize Lala is herself one of these "elite liminals"). The omake's conversation is prompted by how surprised Miia is by seeing three elite liminals in the same place (Yukio and her undine and salamander friends), and Cerea stating they naturally get along well together.
  • "Do It Yourself" Theme Tune: The opening and ending are sung by the girls' voice actresses (the former by the girls at Kimihito's house, the latter by MON's girls).
  • Does This Remind You of Anything?:
    • When Suu and Papi cosplay as Utsuho, with Suu controlling the hands and feet, the others attempt to call them. Suu ends up fumbling with the phone and drops it between her breasts, with all of this happening in public. The phone goes all the way down and then they attempt to call her again. With the phone on vibrate. The people watching from afar would have their noses bleeding by this point. The anime makes it even worse, as Suu's efforts to recover the phone make it look like Papi is pleasuring herself.note 
    • At the extra-species convention, Polt demonstrates the use of an exercise machine to simulate riding a centaur. However, the way she was doing it and her reactions make it look like she's doing the cowgirl position for... something else...
    • At the same convention, the 'Exchange Program Matching Party', where extra species can meet with potential hosts, looks for all the world like a dating service. The hallways are full of human males and female extra species hooking up and openly flirting with each other as they enter soundproof, unmonitored rooms with just a couch, pillows and a blanket in the back, where the hosts can conduct 'private interviews' with the extra species ladies (that day was focused solely on female monsters looking for male hosts). They can even leave forms on their doors detailing their 'preferences' as to what kind of monstergirls they would like to 'interview'
  • Double Standard: Abuse, Female on Male: Largely averted. While Kimihito does take the majority of abuse, most of it is accidental and the girls tend to be apologetic afterwards.
  • Double Standard: Rape, Female on Female:
    • Suu does not understand the implications of what she does to the other girls when she engulfs them, but if they get even the slightest drop of water — or body fluids — on them, she will happily violate them with her amorphous body and tentacles. This is played for laughs and even her victims treat it as nothing but a minor annoyance, telling Rachnera that she'll just have to get used to it.
    • It's impossible to disguise the fact that Rachnera is basically a lesbian rapist. The fact that her assaults involve a lot of bondage with Rachnera acting like a dominatrix is used to play them for laughs, but what she did to Lilith the devil was unmistakably sexual assault. Of course, this is mitigated by how she did it (at least partly) to find out if Lilith was the one threatening Kimihito's life (she had observed the devil was toying with Cerea's mind), and Lilith turns out to be a hardcore masochist and becomes obsessed with Rachnera.
    • Soundly averted in the case of Draco, whose molestation and attempted rape of Miia is in no capacity portrayed as anything other than a bad thing.
  • Double Standard Rape: Female on Male:
    • If any of the girls raped Kimihito, he'd be the one sent to jail while the offending girl would only be deported! Considering how much stronger they are than him (and how horny they can get), it's really impressive that he's managed to fend them off as long as he has! Admittedly, he is eventually selected as a test case for interspecies marriage, meaning that if it does happen, neither of them will be punished, but that would be poor consolation to a rape victim.
    • Chapter 27 might as well be called Double Standard Rape: Female on Male as we learned that lamias have been reproducing by kidnapping and imprisoning men to use as fodder for breeding and played for laughs. This came to an end when the extra-species laws came into effect, forbidding them from doing so anymore. Though that hasn't stopped them with the idea that the lamias that attend the exchange bring back their host. On the topic of Chapter 27, Miia's mother fondles Kimihito's junk twice and subjects him to a poison that forces the victim to become lustful toward Lamias proportionately to their repulsion toward the race (i.e. the less a man wants to have any involvement with Lamias, the more potent it becomes). Since Kimihito has genuine romantic feelings for Miia, it does nothing to him.
  • Draconic Humanoid: Dragonewts resemble Western dragons, complete with wings and tail, though they can't fly. Episode 10's MonMusu Collection also covers their subspecies, which include Ryu-jin (a long-lived wingless type who resemble Eastern dragons rather than Western dragons) and wyverns (an aggressive, none-too-bright type who can fly).
  • Drunk on Milk: Rachnera gets drunk on caffeine (from tea and coffee); this is actually achievable in spiders.
  • Dub Name Change: The English dub of the anime uses the term "demihuman" instead of "liminal" for referencing monster races.

    Tropes E to I 
  • Ecchi: There is topless nudity and lots of fanservice, but nothing more racy than that. This varies sometimes. Even compared to the bold previous chapters, chapter 20 is unbelievably raunchy when you see it for yourself. Then there's chapter 21. For anime only viewers, see episode 10. Yow. Yet even that pales in comparison to Chapter 36. Don't read that with anyone else in the room.
    • Volumes 12 and 13 are pretty light on fanservice, 12 being more focused on story and 13 on action. Volume 14, however, goes absolutely insane with it, with nudity on about eighty percent of the pages, the Farm being a World of Buxom in a World of Buxom, and a climax involving yuri gang milkings.
    • Volume 15 takes it even further, with some scenes only prevented from being hentai by a few strategically placed snake coils.
    • I Heart Monster Girls focuses much less on fanservice and more on humor...aaaaand then comes the story where Kimihito gets turned into a tentacle monster.
  • Elephant in the Living Room: In the Extraspecies convention, Kimihito and Miia check out a room built for those with reptilian attributes. Inside waiting is Draco, who declares that this would be an ideal living space for her and Miia while going on about her imagined future together. Miia and Kimihito instead focus on a lamia tail warmer before leaving, completely ignoring Draco, much to her shock and despair.
  • Emergency Transformation: Lala turns Yuuhi into a zombie with Zombina's tooth so she can come back and continue living after she dies.
  • Emotional Regression: The strong female hormones in a dairy-breed centaur milk will cause those who drink enough of it to mentally revert to infancy and become obsessed with milk.
  • Erotic Eating: Papi can't hold a popsicle on her own without the risk of dropping it, so she asks Kimihito to do it for her. Passersby conclude that he's a pervert who is doing it on purpose.
  • Evolving Credits: The final episode's credits sequence adds Lala to the final shot of the harem cuddling Kimihito in bed. Kimihito's expression also changes from stunned to serene, showing how he's grown used to having the girls around.
  • Exact Words: The Volume 6 color page story has Rachnera testing out various bondage poses on an unwilling Miia and Centorea (she also did it to Mero, but she wasn't exactly "unwilling" about it...). When Miia demands that she "stop doing this kind of stuff all the time", Rachnera agrees that doing the same thing over and over gets dull... so she ties up Miia in a new pose.
  • Fantastic Arousal:
    • Suu does this to Centorea, Miia, and Papi in chapter 10 while trying to get water/sweat off them. Anytime that Suu gets a chance to wrap herself around any of the monster girls, she tends to end up getting a little too touchy.
    • On a more general note, the tip of a lamia's tail. Dragonewts are just as sensitive there.
  • Fantastic Racism:
    • Towards the monster girls. Then if they retaliate, they get kicked out of the country. Though in fairness, it goes both ways.
    • Draco believes that the Dragonewts are superior to everything else on the planet and thus kings of not only reptiles, but all species.
  • Fantastical Social Services: The government runs a foreign exchange program to gradually introduce monsters into human society and promote coexistence. The story begins when a clerical error causes Miia to bunk at Kimihito's house. Her affection for Kimihito soon makes him a poster boy for the program, resulting in him housing several additional monster girls.
  • Fantasy Counterpart Culture: According to the chapters where the girls' mothers come to visit them, lamias live in a pseudo-Arabic country (Miia's mom is dressed more or less as a belly dancer). Harpies live in villages similar to Native American ones. Centaur society is not really documented but it most likely is an approximation of Medieval Europe.
  • Fastball Special: When an orc manages to capture Doppel, who's disguised as Lilith, Kimihito distracts him by throwing the actual Lilith, who's tied up in bondage, into the back of his head.
  • Fee Fi Faux Pas: Played with when the majority of the crew tour a shopping mall for the first time, since the usual supermarket is closed: street vendors go into a panic as they try to hide or at least stop cooking chicken, fish, and even horse as the mermaid, harpy, and centaur come into view. Kimihito hastily contradicts the assumption, at least for the non-vegetarians. Also leads to an associated conversation held by Kimihito to his harem about possible food clashes.
  • Fish out of Water: The world (extra-species and humans) is experiencing this thanks to the fantastic Culture Clash. It is particularly harder for non-humanoid species in human cities (justified because humans have never experienced having centaurs, mermaids and arachnes as fellow citizens, so the cities aren't adapted (yet) to them).
  • Foil: At first sight, Fauns and Satyrs seem to be Foils of each other — the former are fair-skinned liminals with sheep-like features and shy personalities, while the latter are dark-skinned ones based on goats and sexually aggressive to the point they made every girl prior to their official appearance look like prudes by comparison. Notably, during Kimihito's time as a farmhand, a group of each extraspecies girl ended up in a conflict of sorts where the Satyrs tried very hard to get into his pants (let's just say group-coordinated Invocations of blatant Erotic Eating situations is the tamest they got up to), while the Fauns offered to help him with his tasks, so the Satyr girls wouldn't catch him alone. This was a Subversion, however, because the Fauns turned out to be pretty perverted themselves, just a lot more covert and polite about it, given how several of them jumped at the chance of getting "milked" by him under the flimsiest of justifications.
  • Food Porn: Later chapters feature entire full-page panels devoted to showing off mouthwatering food.
  • Forced Orgasm:
    • In her debut appearance, Kii the dryad inflicts one on Papi by wrapping her in vines — which of course occurs in a BDSM fashion — and tightening them until she orgasms. Papi, Kimihito, and Suu inflict one on Kii in turn by sucking and groping her breasts in an effort to remove the fertilizer-saturated waternote  from her body.
    • Suu the Slime will frequently inflict this on the other girls in the household if she gets dehydrated or gets called on to takedown Rachnera whenever Rachnera, Centorea, or Miia try to sneak into Kimihoto's room for some late night nookie, (as Centorea takes down Miia, and Rachnera takes down Centorea).
    • Kimihoto himself has inadvertently done this to Miia on one occasion where she fell asleep in his bed after wrapping herself around him, but being a Lamia, she unknowingly nearly chokes Kimihoto to death in her coils. The only way he was able to escape was by tugging on the tip of her tail, causing her to loosen her coils and climax soon afternote 
  • Foreshadowing: The author's note in Chapter 8 regarding Suu's appearance says that some of the other most requested monster-girls were a spider girl, a dullahan, a mermaid, a plant girl, and a dragon girl. All of which end up appearing later in the manga.
    • The anime does this a lot, to the point that it sometimes gets into Late-Arrival Spoiler territory for people who haven't read the manga.
  • Forgetful Jones: Harpies as a whole have terrible memories. Papi can't even remember Kimihito's name, only calling him 'hubby'. Eventually, he realizes her memories are forgotten after her third step or so, and has her stop walking to explain more about the situation.
  • Formula-Breaking Episode: Chapter 74 mostly takes place in a fantasy world, which Ms. Smith, Kimihoto and the gang were all transported into via a grimoire (or rather, their minds were transported), where everyone but Kimihoto acts like a high school student. Unlike previous chapters though, it’s no hallucination.
  • Formula with a Twist: This series put a spin on the Harem Genre by making each of the girls in the protagonist's Unwanted Harem some form of Cute Monster Girl, with much of the show's intrigue and comedy coming from the Deliberate Values Dissonance, Bizarre Alien Biologies, and mating habits of the various girls. It was popular enough to inspire a number of "monster girl" works, both in the harem genre and others.
  • Freeze-Frame Bonus: At the end of every episode in the anime, a set of descriptions for subspecies of creatures representing the main heroines is displayed. However, it's only up for a few moments, necessitating pausing if one wants to read their descriptions.
    • In Episode 11, when Polt is shown running past Manako, D can actually be seen in the background.
    • Episode 12 has a few of them, for example the silhouette of Muromi hidden in the splashes when Kimihito floats down the river, and also, in the shopping district sequence, a sign reading NIKI KETTEI.note 
  • Friendly Neighborhood Spider: Rachnera is one of the many monster girls in the Unwanted Harem of Kimihito. She hated humans following her experience with her original host family, until she met Kimihito, eventually fell in love with him, and made friends with the other monster girls. Rachnera is aware of her own strength, so she's very careful with Kimihiko, also saving him a couple of times.
  • "Friends" Rent Control: Justified; all expenses needed to house the many people that live with Kimihito are paid for by the government as part of the exchange program. The associated rising food expenses versus a constant income, on the other hand, comes to a head in Chapter 25... by the end of the chapter, it continues to be played straight.
  • Full-Boar Action: A wild boar appears out of nowhere in Chapter 21.
  • Funbag Airbag: A pretty literal case when Kimihito meets Mero. He catches her before she can crash into a telephone pole, with her breasts cushioning the impact to his face.
  • Funny Background Event: (Episode 4) While Miia, Centorea and Kimihito discuss what to do with Suu, she already plays TV console tennis with Papi.
  • Genre Savvy: The Crash-Into Hello above? Centorea believes all stories in Japan have their true love met this way, particularly if they are eating a piece of toast. This is a common staple in anime.
  • Gentle Giant: Tionisha, but also all the ogre subspecies according to ep. 9's end card. Despite their size and strength, they're very laid back and not aggressive. Exaggerated with the Gigantes: 10 mt./30+ ft. girls ashamed of their nudity (almost nothing fits them) and so afraid of hurting someone by accident that they'll stand still for hours. Awwwww.
  • Giving Up the Ghost: More than one victim of Miia's cooking, as well as Miia herself when she finally comes across Lala's head and later watches Lala drink tea (read: pull off her head and pour the tea down her neck).
  • Godiva Hair: Frequently in the anime, so it can avoid showing anything that's fine in manga form and not-so-fine on television. Also the only form of covering doppelgangers wear since they use it to transform.
  • Gonk: Male Centaurs are so ugly and brutish that the only way many of the females will ever mate with them is if they are put in the mood by a handsome human male. Much in the same way 'teasers' are used when breeding racehorses.
  • Gratuitous English: The English subtitle below the series' kanji says "Everyday that there is a monster girls."
  • Grievous Harm with a Body: How the girlfriend of the racist asshole couple in volume 1 gets her comeuppance without directly getting punched: Kimihito punches her boyfriend hard enough to send him crashing into the wall... with her standing directly in the path of flight.
  • Half-Human Hybrid: Due to the monogendered nature of their respective species, Miia and Papi are half-human; Chapter 29 reveals that Cerea also falls under this.
  • Hannibal Lecture: Lilith, bound to a tree by Rachnera, tries this on her by calling her basically a frightened little girl hiding behind her tough outer shell. Not only does it not take, but it mostly just serves to make it that much worse for herself. Then again, the fact that she reacted like that does opens up the possibility that Lilith may have struck a nerve.
  • Happy-Ending Massage: The eel mermaid masseuses in Chapter 35 go straight for their clients' erogenous zones and don't let up, for a PG-13 version.
  • Hard Truth Aesop: Brought to us by Rachnera no less. As Centorea and the audience learns, It's more condescending to pretend everything is fine, than admitting that you have issues with a new friend or roommate. The sooner you admit your issues the better off everyone is, because then you and the other party can start working towards addressing them. She also convinces Centorea that she and Miia had every right to be wary of her based on appearance alone because she doesn't just look dangerous, she is dangerous — especially to humans whom she can easily ambush, overpower, restrain and kill. With the reveal of her Back Story later on, we know this is Rachnera's Internalized Categorism talking, but it's still quite jarring to hear when Centorea had said earlier in the chapter that they as Extraspecies should know better than anyone how much being judged for their appearance hurts.
  • Harping on About Harpies: Papi and her mother. Episode 2's MonMusu Collection also covers several harpy subspecies, such as land animals, the harpy version of birds such as emus and ostriches, adapted for terrestrial life; poultry, the harpy version of chickens; and raptors, the harpy version of eagles and hawks.
  • He Is Not My Boyfriend: When Meroune innocently asks Centorea if she's dating Kimihito in chapter 12, the latter replies this way. Not that they'd mind being his girlfriend/wife though.
  • Headbutt Thermometer: Centorea demonstrates this to Suu, who then performs this on Kimihito. It doesn't quite work as well as Centorea intended, mostly because Suu almost drowns Kimihito and just repeats what Centorea said—that is, her body temperature.
  • Headless Horseman: A female Dullahan named Lala shows up, minus her steed.
  • Heart Beat-Down: The ending of the anime opening credits has all the girls combine this into one giant attack and throw it at Kimihito.
  • Heroic Sacrifice: Subverted. Kimihito takes the hit when the purse snatcher tries to slash Centorea with her sword. Luckily it's just a (very sharp)fake. While Centorea knew it, Kimihito did not, making his attempted sacrifice completely genuine.
    • Meroune injures her tail when she saves Kimihito from the traps in her mother's throne room. Luckily she's able to make a full recovery.
  • Hidden Purpose Test: In Chapter 29, it turns out Centorea's mother challenged her to a duel not because she disapproved of Centorea's relationship with Kimihito, but to prove that the centaur race's old custom of only breeding with the strongest centaurs was outdated, since Centorea fought her to a draw, despite the latter's father being a "weaker" human.
  • High Collar of Doom: "Cobra Miia" had one resembling a cobra's hood.
  • High School AU: The ''Grimoire High School Arc" focuses on the main/side characters enjoying a normal high school life together after a grimoire spell was cast.
  • Hoist by Her Own Petard: Happens to Miia twice in chapter 12:
    • The first time, she notices Meroune's clothing keeps slipping off due to a mermaid's natural sliminess. So Miia plays with Suu to get slimed up too, but Kimihito just tells her to take a bath.
    • The second time she turns down the temperature to make Meroune feel cold, despite the fact that Miia herself doesn't like the cold. Then Mero mentions that compared to the temperatures in the deep parts of the ocean, the AC feels nice to her.
  • Hostile Show Takeover: Downplayed. In the Anime episode that introduced MON, the ending theme(focused on MON) is played as the opening theme with the regular opening theme(focused on the main cast) serving as the ending theme.
  • How We Got Here: Chapter 6(episode 3 of the anime) starts with Miia, Papi, and Centorea, fighting over Kimihito, each saying they'll be the one he marries. It goes back to earlier that day to show how this happened: Ms. Smith's announcement that Kimihito must marry one of them, and the effects of the full moon causing them to lose control of themselves.
  • Human Subspecies: Both the politically correct, and actual classification, of the "monsters" of the series. For the most part they act like humans with physical quirks; in fact, humans and some extra-species have always reproduced together and the zombie extra-species is, in fact, composed of actual former humans anyway.
  • Hurricane of Puns: The first volume of the English manga has so many animal puns. While present in the second volume as well the amount of puns seem to have been drastically reduced.
  • Hypocritical Humor:
    • In chapter 2, Miia yanks Kimihito into a dressing room to show off some bras, which he is clearly uncomfortable being in. He rushes out after seeing her topless, and accidentally yanks her panties away, which seem to be a thin triangular shaped piece of clothing. She then says only a pervert would steal a girl's panties, while completely ignoring the fact that she constantly teases him and goes topless around him, putting him in those perverted situations against his will.
    • In Chapter 19, Miia is indignant when Mero introduces her to a sea snake, believing she's doing so just because Miia's a snake. This despite Miia making fun of the other girls by comparing them to sea animals.
    • Miia, Mero, and Rachnera say they thought Dullahans were made up. They're not ones to judge, being a snake-lady, mermaid, and spider-woman respectively. As Kimihito points out.
  • Idiosyncratic Episode Naming: Every episode of the anime is titled thus: Species [number] - Daily Life with [plot description].
  • Imagine Spotting: Kimihito in particular is prone to this.
    • In episode 2, Kimihito notes that Miia's image of him looks nothing like him.
    • In episode 3, Centorea talks about the proud centaur race and behind her a group of armored centaurs are visualized. Kimihito asks "Are those Stands, or what?".
    • In episode 6, Kimihito comments that Miia's Naked Apron fantasy has nothing to do with cooking.
    • In the final episode, Centorea tastes some carrots and extols their virtues during a Disney Acid Sequence. Miia, who is not even near her, points out that her poor taste buds are only one of the reasons behind her terrible cooking. Behind her, Rachnera wonders who she's talking to.
  • Immodest Orgasm:
    • The first is before you're even ten pages into the story, too (or 3 minutes into the Anime).
    • A Running Gag is that Suu is often prone to causing the other girls to have them whenever she gets thirsty.
  • Impossibly-Low Neckline: Yukio, the Yuki-onna owner of the Arctic Inn.
  • Improbable Food Budget: Averted in chapter 25. With Lala's addition to the group, Kimihito discovers that he can't afford to feed everyone. Later played straight and justified, as food expenses are also paid for by the government.
  • Improbably Female Cast: Aside from the Orcs in Chapter 11, the male centaurs in Chapter 29 (in a flashback), Sebasstian and Flounnder in Chapter 34 and Curie's father in chapter 50, every single Extraspecies seen has been female. That said, Lamias and Harpies at least are a One-Gender Race. More males do show up from time to time, but just about every character with lines is female.
  • I'm a Doctor, Not a Placeholder: Centorea's response to Mero's suggestion that she help carry a large quantity of groceries: "I'm a knight, not a packhorse." Her response to Kimihito asking her to do it? "As you command, milord!" and strapping everything to her back.
  • I'm Taking Her Home with Me!:
    • In chapter 19, Tionishia mistook "touching the dolphin" with "abducting it from the pool".
    • In Chapter 33, Papi and others help on a farm and she absolutely falls for the baby chickens to the point she won't leave the farm without them.
  • Innocent Fanservice Girl: Played with. Most if not all of the Monster Girls in the series have this to at least a minor extent and are universally at least less embarrassed by it than most human women would be. Kimihito comments on how the mandatory mixed bathing policy of the hot springs they were at had scared away all of their female customers, and all of the members of his harem react with surprise that this would be the case, or otherwise express openness or indifference to the concept of mixed bathing, which later gives them the idea to combine that knowledge with Centorea's mixed bath dating idea she had when discussing ways to bring in customers and have the resort feature interracial dating meetups in the onsen. That said, most monster girls are quite aware that they turn men on, just not always aware when they are doing so.
  • In-Series Nickname: Kimihito is rarely called his real name, as each of the girls have their own nickname for him.
  • Instant Sedation:
    • Played with when Ms. Smith uses darts meant for Extraspecies. So when Kimihito was hit with three of them she was glad to see that he was still fine.
    • Straighter example in Chapter 27 with lamias' neurotoxin. Can be taken orally. Several hours of sleep with no risk of overdose and hardly any ill effects. Or maybe the one administering it doesn't care about others' well-being. Rachnee later pays her back for the hangover.
  • Internal Deconstruction: The point of the manga has always been fanservice with monster girls, with the manga eventually admitting that almost all girls in the Homestay program are just looking for a human boyfriend. Lampshaded with Rachnera acting as a receptionist and bluntly asking men what kind of monster girl they are attracted to in order to match girls with homes. Chapter 65 points out how seriously the actual care and environment of the girls matter a lot and require things that most people don't have. The Dating Pool Trio, a group of average men, realize that their homes would actually be terrible for the girls they want.
  • Interrupted Intimacy: If it ever looks like one of the girls is about to do it with Kimihito, you can count on another one showing up to stop them.
  • Intimate Healing: In Chapter 13, many of the ladies' suggestions to help Kimihito get over his cold tend to degrade towards this. In the end, what actually works is another example: Suu gives him filtered water out of her body, by breastfeeding him.
  • Ironic Echo Cut: In Chapter 40, Doppel unleashes what's implied to be her true form on the Orc Leader. Immediately following is a cut to Liz and Kinu playing the Call of Cthulhu tabletop RPG and coincidentally summarizing the events that had just occurred.
  • I Want Grandkids: Miia's mother. Also applies to the entire lamia race; lamias require human men to be able to reproduce, so they are often forced to kidnap men and press them into becoming the father of the next generation of lamia. The Extraspecies Exchange Act stopped this kidnapping, so each Lamia tribe sent out a representative to find (and seduce) a man so he would come willingly. Miia is the representative of her tribe.

    Tropes J to P 
  • Just a Kid: Papi and Suu are treated more like Kimihito's little sisters than romantic rivals by the other girls in the household. Rachnera even volunteers to "babysit" them when Miia, Meroune, and Centorea visit a gym built specifically for extraspecies like them.
    • In the English translation, Kimihito refers to them as "the kids" at least once.
  • Karma Houdini:
    • Despite the fact that the law is very clear about sexual intercourse in the host home, Miia and the others all routinely make passes at or otherwise force themselves onto Kimihito. He is always the one taking all the heat and being reminded and threatened about the consequences (though admittedly this happens only a few times and is Played for Laughs as it seems likely Smith wouldn't bother enforcing the rule with him anyway), and yet the girls are never reprimanded for THEIR behavior or told to have any sort of self-control (admittedly their behavior is also rarely ever seen by Smith, and Kimihito actively covers for them). This aspect vanishes as the law gets taken less and less seriously over time.
    • Smith repeatedly shirks her duties as an exchange coordinator and makes life harder for Kimihito while rarely ever suffering any punishments for it. She brought Miia to live with him by accident, dumped more exchange students on him (some without his consent), and even turned him into a guinea pig for inter-species marriage (though this was an offer rather than a demand). The only consistent comeuppance she suffers for any of this is that she is overworked and underpaid. There was also the time she ended up with a cold without anyone to take care of her after she shirked her duties and falsely claimed she needed to take care of Kimihito.
  • Knight of Cerebus: There are frequently "arc villains" so to speak who suddenly appear to represent the darker side of a sudden monster-human warming in relations. This is always ultimately subverted, however, as they inevitably reveal quirks that destroy their credibility, suffer a Humiliation Conga, or join the harem's antics the chapter just after, with everything forgotten and wiping off the Cerebus Syndrome along the way. These are not mutually exclusive.
    • The Orcs seem to be this in chapter 11, despite being quite a bit sillier than most examples, but that chapter turns out to be an Out-of-Genre Experience.
    • Rachnera served as a slightly straighter example. Not only is she more monstrous than most of the other girls, she quickly and easily ties up the chapter's antagonist in a single panel. Her backstory, revealed in the next chapter, also depicts a darker side to the exchange program: her host family illegally sold her to the director simply because they were expecting a more humanoid extraspecies, such as the cat girls that the media tends to focus on (although the truth proved to be not quite that simple: they honestly thought the director was part of the exchange program, and sold Rachnera off because she accidently injured her daughter). However, looks were deceiving: Rachnee's far from evil, more bitter than anything, and she ends that very chapter with joining the group.
    • A straighter example is the dragonet, Draco. Not only is she a fearsome sight, but she has the sheer, high-octane crazy to back it up, kidnapping and almost raping Miia. Unlike Rachnera, she has no Freudian Excuse for her actions, and unlike the orcs she's competent and played deadly serious.
    • The Dullahan, Lala, makes her first appearance grabbing Kimihito by the notch in her scythe. Like Rachnera, however, she ultimately turned out to be (relatively) harmless: she plays up the 'doom and gloom' angle because she enjoys playing pretend, and just like Rachnera she joined the group when all was said and done. Except her chuuni act covers up her control over death.
    • Octo the scylla is initially portrayed as a manipulative sea witch, responsible for human-mermaid elopement becoming a growing problem in mermaid society, even going so far as to kidnap Meroune. Then it turns out Octo wanted a chance to talk with Mero alone, in the hope that she could put a stop to the rumors about her, and Mero came willingly. Octo's not responsible for the growing rate of elopement (which is all down to the mermaids themselves), doesn't have any supernatural powers, and just wants to be left alone.
    • Perhaps the scariest example so far is Mero's own mother, queen of the mermaid kingdom. She personally instigates and spreads evil rumors about Octo, and also blows the mermaid-human elopement problem way out of proportion, in order to create a huge political upheaval that would result in the re-segregation of humans and extraspecies races. Why? Because it would be so tragic. She's also revealed to have been cheating on the mermaid king (Mero's father) with a human boyfriend, and said schism between humans and extraspecies would separate the two of them, adding more to the tragedy. Then to top it off, she nearly drowns Kimihito and almost kills Mero, her own daughter in the process when she loses control of the various death traps she had set up. She's the villain that comes the closest to causing harm on a very large scale and multiple major character deaths in the series. Of course, as per usual, as soon as she is foiled, all is fixed and forgiven, and the status quo is mostly maintained.
    • The Colossal Slime in Chapter 54 & 55 provides the straightest example yet. She's a Kaiju of a slime whose only goal is to absorb Suu in order to gain access to all the knowledge and experience the latter has accumulated while living with Kimihito, a process that would effectively kill Suu as an individual. She's not played for laughs or titillation at all, and even after being defeated she nearly kills Kimihito and Suu.
  • Lady Land:
    • The farm gets turned into this at the end of chapter 59, with the satyrs taking over the responsibility for milking the fauns and minotaurs, the fauns doing the household chores, and the minotaurs continuing to handle all the heavy lifting. Though they're all happy to invite any handsome men over for a visit.
    • Miia's hometown, the Lamia village, consists almost entirely of a One-Gender Race. They're all fairly excited that Miia brings back a virile human male in Chapter 60. The older lamia do have a resident man to attend to their desires, but he doesn't go for the younger generations.
    • Chapter 67 shows that the Arachne race is also all female, and Rachnera was sent to see if their race can live among humans without sacrificing what they are.
  • Laser-Guided Karma: Chapters 65 and 66 have a double dose.
    • In chapter 65, a lecherous rowdy man at Yukio's inn and bathhouse is getting too close and pushy on three Liminal ladies, who aren't appreciating his actions. He is first scared off by three men who play a trick on him, and in chapter 66 his actions were alerted to the lifeguards and security, who set a trap for him and when he falls for it, gets kicked out of the event and blackballed from reentry.
    • Also in chapter 65 the three humans who came to the event looking for a liminal to stay at their homes. After they saved the liminal ladies from aforementioned lecherous man, the ladies are thankful for the help and they find they will make very nice partners in the homestay program.
  • Latex Perfection: Suu's shapeshifting abilities come in very handy, able to form perfect human legs for Meroune's disguise and perfect human arms for Papi's disguise. Unfortunately, said legs and arms are under the sole control of Suu, who can be scatterbrained at the best of times.
  • Lecherous Licking:
    • Miia does this to Kimihito under Lunacy, as does her mother when she decides to take Kimihito for herself. It helps that Lamias have Overly Long Tongues. Suu also occasionally does this to any girl covered in liquid.
    • Rachnera does this to tease a bound-up Kimihito in her introduction chapter.
  • Leg Focus: When asked what he likes best in a woman in an omake, Kimihito says "legs". Going by his response to Rachnera in the main story when he first meets her, the species of the legs in question doesn't seem to be foremost on his mind.
  • Lethal Chef: Anything Miia cooks is almost certain to make you sick or even pass out from just the smell. At first it was thought to be due to her just being a horrible cook, adding ingredients to the food simply because they have the same color or adding different ingredients because they have similar-sounding names. But then it's also revealed that since she's a carnivore, she has fewer taste buds and can not judge her own cooking.
    • Exaggerated in the anime, due to Sequence Break. In the Manga, Miia's first culinary nightmare occurred before Suu was introduced (in fact, Suu first entered the house because she was attracted to the smell of Miia's cooking). In the anime, Miia's first Lethal Chef attempt occurs after both Suu and Meroune had been added to the household, so Suu was shown being affected by it (normally she's the only one who can eat it without any side effects, due to being an Extreme Omnivore). Albeit it may simply be that Suu was playing along and mimicking the actually sick girls, since the "soul" coming out of her is solid unlike theirs and is also smiling.
  • Limited Wardrobe: Averted by the most fashion-conscious girls (Zombina, Tio, Manako, and especially Miia). Justified in that many of the girls need specially modified clothing to be able to wear them properly. (Meroune's skin is constantly coated in a slippery film, Papi has large, feathery wings instead of arms, Suu can only wear waterproof items such as a raincoat, etc.) Smith, outside of her work uniform, is too lazy to wear anything else than a tanktop and panties at home. Doppel's always nude, and Polt's generally in athletic wear. The standard styles of the other girls:
    • Papi: Booty shorts and tank/tube tops
    • Centorea: A sort of skirt/drape for her lower half, and a light-tan sleeveless blouse, often with neckware
    • Suu: A yellow raincoat and boots... or a bucket
    • Meroune: A black gothic lolita style dress or swimsuit
    • Rachnera: Detached sleeves and halter tops
    • Lala: Dark purple/black cloaks
  • Little Bit Beastly:
    • All the girls shown during the 1st chapter, where the news reporter states that the program was a "huge success" and that the world hasn't changed much from it. It explains quite a lot about what happens to our poor protagonists, who don't fit into this category in the slightest.
    • We actually get to meet an extraspecies girl who fits this category for the very first time in chapter 17: a Kobold (dog-girl), and a rather genki one at that. Since then, more and more have been showing up: dragonets, dryads, and devils all fit this category, culminating in a dullahan: just going by the manga, you'd never know she's not human until her head comes off or you get a look at her eyes (in full color, however, her skin's an obvious giveaway).
    • Then after them, we get yuki-onna, nine-tailed foxes, a minotaur, a faun, barometz, and lizardfolk.
  • Littlest Cancer Patient: Shows up, and is dealt with in the story's normal off-the-wall manner. Lala 'cures' her with one of Zombina's stolen teeth, killing her and turning her into one of the undead. It works out fairly well, all things considered (she certainly doesn't have to worry about terminal diseases any more), but is a bureaucratic nightmare.
  • A Lizard Named "Liz": The names for most of the Monster Girls are all indicators of their species.
    • Each of the Cute Monster Girls in Kimihito's harem has her name derived from her species name — Miianote  from Lamia, Papi from harpynote , Centorea from Centaur, Suu from Slimenote , Meroune from Mermaidnote , Rachnera from Arachne, and Lala from Dullahan.
    • It isn't limited to the main cast either, see also: Zombina the zombie, Doppel the Doppelgänger, Draco the dragonet, Yukio the yuki onna and, yes they use the exact trope name with Liz the lizardwoman.
    • Even Ms. Smith qualifies, her given name is Kuroko (kuro meaning black and ko being a feminine suffix) and she is a female MIB.
    • An invoked trope for both Suu and Kii, who were named by Papi. She named them both, but was too bird-brained for more complicated names. "Suu" is the first part of the Japanese word for Slime, as with above, and Kii is the Japanese word for tree.
  • Loophole Abuse:
    • The Interspecies Protection Act has a few, namely, the "Humans can't attack monsters" and vice-versa law, which can be exploited by criminal monsters.
    • When Miia gets insulted a second time by the racist couple in chapter 2, she remembers that she can't attack humans. However, that doesn't stop Kimihito from punching both of them in the face.
    • This particular abuse caused some, currently unknown, changes to the Extraspecies Exchange Laws.
    • In Chapter 14 and episode 6 of the anime, a director tried to use the loophole of recording documentary of Kimihito's female guests to get away with taking uncensored film recordings, Miia's shed skin, and Papi's egg to sell for money. Good thing Suu and Kimihito were there.
    • In Chapter 16, a man tries to use the 'monsters can't harm humans' rule for...VERY bad reasons. Unluckily for that guy (and luckily for everyone else), Rachnera doesn't give a shit.
    • Papi and other Harpies lose their memory after taking three steps. As long as they can avoid that however it will last much longer.
    • The Interspecies exchange act put a stop to the Lamias kidnapping and forcing themselves on men to reproduce. However it doesn't say anything about their exchange students getting married and bringing a man back to act as the "communal husband".
  • Lost in Translation: Papi refers to Kimihito as "Goshujin" (ご主人) which can have multiple meanings depending on the context. In the official translation, this is rendered as "boss" while in most Scanlations it's translated as "husband." However, other interpretations include "master" (as in master of the house, or landlord) or "owner" (as in the owner of a pet, or owner of a shop). Given that Papi is a tenant of the Kurusu residence as part of the inter-species exchange program and that her romantic interest in Kimihito is more of an afterthought compared to the other girls, the former is most likely the intended translation, but "landlord" doesn't roll off the tongue very well, and "master" has a whole other meaning tied to it.
  • Lower-Deck Episode: Chapter 65 revolves entirely around a trio of boys who came for the mixed-bathing-dating in Chapter 64, with Kimihito and the girls being mostly absent outside of two quick scenes near the end.
  • Lunacy: The full moon apparently awakens a monster girl's more primal instincts, snd wouldn't you know it, it comes the night Ms. Smith introduces the inter-species marriage addendum. Poor Kimihito spends the whole night trying to avoid some unwanted monster sex.
  • Made of Iron: Kimihito can take a lot of punishment. Subverted when Lala explains that in a lot of cases he does die from his injuries but is too stubborn to stay dead. Lampshaded in Chapter 38, where the hospital doctors can't figure out how he's uninjured despite the daily abuse.
  • Male Gaze: A plethora of them happen in chapter 43 at Polt's gym. When Polt and Miia show off some stretches, the human male clients are shown thinking about and enjoying the ladies' large and bouncy breasts.
  • Marry Them All: Suu thinks this is probably the best way to solve Kimihito's "harem problem." Of course, whether or not she fully understands what marriage is is an open question.
  • Mars Needs Women: Gender-flipped. Lamias and harpies are both female-only species and require human men to mate with in order to perpetuate the species. Chapter 27 reveals that lamias had previously kidnapped men as sex slaves for this, but were forced to stop with the species exchange program and Miia's original purpose was to find a man to bring back as a communal husband for her village. Alraune, from Episode 11's MonMusu Collection, are similar, requiring other species to propagate.
  • Marshmallow Hell:
    • Kimihito is often put into this by Miia and Centorea.
    • Tionishia gets in on the act in Chapter 22.
    • In Chapter 29, he found himself drowning between Cerea and her mother's breasts while they were making up after their duel.
    • In Chapter 36, it's Octo's turn to smoosh him.
    • In chapter 41, while his head is on Tionishia's lap, she leans over to grab something and nearly kills him with the weight of her breasts.
  • Mass "Oh, Crap!": In chapter 26, Centora, Miia and Papi have one when they realize their mothers are coming to visit.
  • Maybe Magic, Maybe Mundane: Due to the extra-species highly resembling creatures from myth and fantasy, it's sometimes assumed in-universe that they have supernatural powers, such as the rumor that Octo can grant wishes. However, as noted under deconstruction, the series bases as much of the extra-species' features in real-life science as possible, as so far no species has displayed any supernatural powers, save for the Dullahan race, which Lala shows at the very least can teleport and can manipulate death. Curie's father is also another specific exception, with his soul possessing his daughter (who is eventually exorcised by Lala) but Curie doesn't display any obvious supernatural powers otherwise and just follows the standard vampire templates explained by Ms. Smith.
    • That being said, Chapter 74 explicitly confirms the existence of magic, when Kimihoto and the girls get sucked into a fantasy world created by a grimoire that Ms. Smith confiscated.
  • Meaningful Background Event: In Episode 11, if you're paying close enough attention, you can spot "D" in the background of at least one scene before she actually appears.
  • Mercy Kill: A typically weird and light-hearted variant. When there's a dedicated effort to make the undead welcome, productive members of society, 'curing' terminal diseases with zombie bites can become quite tempting.
  • Mermaid Problem: Not an issue for any of the girls (Mero, and Miia with her similar body structure, have genitalia on the ventral portion of where their human halves transition into tails), but referenced by some hecklers.
    • As early as the first volume, Miia is shown lying on a bed, (almost) completely naked, just wearing "panties" (actually an adhesive triangle of cloth that sticks to her very human genitalia). From what you can see, her snake tail has a lengthwise crease where it connects to her human waist, making it look like Miia had legs, but they then fused together to form the snake part of her.
    • Discussed a bit during the gym chapter: Centorea doesn't have anything between her front legs, but still wears clothing there because to not do so would make her look naked from a human perspective, despite not actually showing anything.
  • Mistaken for Cheating: Cathyl believes her home-stay carer/boyfriend is cheating on her when she hears him talking to several girls in the barn late at night. Kimihito later recites off their names, explaining that those are the names of the farm's sheep and cows.
  • Moment Killer: With such a large harem of extremely jealous girls, it's assured that as soon as Kurusu gets into a situation that starts turning romantic, one or more of the other girls will interrupt it.
    • Chapter 64 has the whole gang doing this as a part-time job in Yukio's onsen, gently stopping the guests from getting too frisky inside the inn and the bath.
  • Monster Girl of the Week:
    • The series takes this formula from chapters 19 to 22. In order, we get a dragonewt, a dryad, a devil, and a dullahan. Notice a theme? You should— the first three are Red Herrings for an anonymous assassin going by "D," and while "D" was initially determined as a fake in Chapter 22, a SECOND letter comes in. At first, it seems to be an actual threat, but then in Chapter 24 it's revealed to be a Dullahan with a penchant for long-winded speeches and pretending to be the Grim Reaper.
    • It takes this formula again during the vacation arc in chapters 31 to 34, where we get a yuki-onna, a nine-tailed fox, a minotaur, a faun, a pair of barometz and a lizardwoman.
  • Mood Whiplash:
    • The introduction of the Orcs has a good amount of this. First they enter the store, armed with AKs, and take the workers as hostages. Then they make their demands which are... to get OrcXElf/Princess/Royalty/Slave/everything pornography. Hm. Maybe these guys are not so threatenWTF?! Did one of them just unload their bullets into the stomach of a police officer while taking another hostage as a rape victim?! The officer and the "rape-victim" are actually part of MON, make it out easily, and end the threat, but still, that was one hell of a mood change.
    • In Chapter 18, the monster girls believe Kimihito is cheating on them with Ms. Smith. Hijinks ensue as they follow their "date" until they learn the real reason for it: Kimihito received an anonymous death threat and they're trying to flush out the perpetrator.
    • Chapter 22 has the reveal that "D" was Doppel all along. The group laughs it off as a well-intentioned plan gone horribly awry. Then a second letter from a REAL threat comes along, and everyone assumes it's just Doppel again. The real clincher is a Dullahan hooking Kimihito by the neck with her scythe.
    • Chapter 38 goes from Lala hilariously visiting Kimihito in the hospital to her having to figure out whether to prevent the death of a terminally ill girl she meets. For just a moment she drops the overblown grim reaper act and legitimately doesn't know what to do. She eventually comes to a solution though. See Take a Third Option below.
  • Morton's Fork: Kimihito is presented with one at the end of chapter 5. Ms. Smith says the government is going to try out inter-species marriage, and decided he was going to be the test case. So she tells him to marry one of the girls living with him. Since all three of them are Clingy Jealous Girls however, this doesn't work out well for him as they all try jumping him at once in the next chapter, once the full moon puts them in the mood.
  • Mum Looks Like a Sister: Miia's, Papi's and Centorea's mothers all look barely older than their daughters. While for Papi's mom this is to be expected (Harpies' petite bodies allow them to fly), no reason is given for why Miia's and Centorea's mothers look that way and is even lampshaded in the case of Miia's mother.
  • Mundane Utility: In chapter 27 Kimihito decides to thoroughly clean the house before Miia's mother arrives. Papi uses her wings as a feather duster and Suu turns into a Roomba to clean the floor.
  • Mushroom Samba: In Chapter 45, when Kimihito and Centorea get home, they find that the interior of the house has somehow turned into a giant dungeon, Papi is now a tiny fairy-harpy, and Suu is a giant monster slime. Mero reveals that it's all a hallucination caused by inhaling the spores being given off by a mushroom-like person that Papi brought home. She managed to avoid being affected because she breathes mostly through her gills, and the spores aren't transmitted through water.
  • Naked People Are Funny: The nudity is played for titillation, but most scenes also invoke this mentality. Hijinks often ensue because someone got naked where they weren't supposed to.
  • Neck Snap: Kimihito is on the receiving end of this courtesy of Miia during the shedding scene. He's better in the next scene, of course.
    • Miia performs a less severe version on Centorea in Chapter 12 to snap her out of a medieval fantasy with Mero. Centorea is still massaging her neck several panels later.
  • New Powers as the Plot Demands:
    • It's nearly becoming a running gag for Suu to randomly turn out to have whatever power is needed this week. Of course, Suu is a previously unknown species, so this could simply be a case of powers no one knew about, rather than spontaneously displayed.
      • Suu suddenly shows off a whole raft of new imitation-based powers in Chapter 13, including shapeshifting into a fairly convincing duplicate of another person.
      • In the same chapter, shown briefly, is what seems to be a empathy link ability, as Suu was able to suddenly experience every sensation Kimihito was feeling while sick by touching his forehead with the tip of the slime feeler on her "hair". In the next chapter, it was shown that this extends to being able to read minds in general, as she did to expose the director's true nature to the rest of the cast.
      • In chapter 18, Suu imitates clothing and limbs to disguise the other monster girls as humans.
      • In chapter 20, Suu turned into a Kaiju and apparently doing so makes her smarter, though she had to fall into a pile of experimental fertilizer first and it proves to be a one-off event (though she would much later get a similar one-off transformation via ingesting royal jelly from honey bee monsters).
      • The intelligence boost returns in chapter 31 when she absorbed the minerals from the hot spring they were visiting.
      • As of chapter 25 Suu can detect poisons and changes shape to indicate them. This despite being apparently immune herself (though it does "poison her words", as observed by Kimihito). Also she can spit ingested poisons at others.
      • As of chapter 30, Suu is also apparently able to heal injuries to a certain extent, shown when she healed the torn skin on Kimihito's finger simply by putting said finger in her mouth (although the kind act was overshadowed by her smothering and once again nearly drowning him). As of yet, it isn't clear whether this ability only functions for small injuries like the torn skin on the finger, or if it would work for larger injuries as well.
    • In chapter 18, Rachnera reveals that she can use her thread like a cup telephone.
      • In chapter 32, Rachnera forms clothing from her thread almost instantly. Kimihito promptly lampshades this by saying that it's kind of ridiculous.
    • While pursuing Miia and Kimihito, Miia's mother suddenly reveals that she has Pit Vision which lets her track via infrared heat.
  • Nice Job Breaking It, Hero:
    • In general, the girls tend to break windows and doors anytime they suspect Kimihito of trying to get intimate with one of the other girls.
    • In chapter 12, Kimihito has Meroune in a Bridal Carry, causing Miia to get insanely jealous and slam into them to break them apart. Turns out that he was just carrying her to the second floor so she could see what was up there. Miia also breaks Meroune's wheelchair in the process, so now he has to carry Mero that way for the rest of the day, something the former is not pleased about.
    • Lala performs an Emergency Transformation and turns an ill girl into a zombie so she can live after passing away. Unfortunately she used one of Zombina's teeth landing her, and the rest of the MON squad in hot water. Oops.
    • Dopple tries to make Draco apologize to Miia, making sure they'd run into each other and providing the perfect opportunity. Unfortunately she arranged for Liz, who Draco had also angered, to show up so she could reconcile with her too. Making it look like shes going behind both their backs getting them even madder at her.
  • Ninja Log: Another of Rachnera's many abilities (see New Powers as the Plot Demands above) that shows up in chapter 55. At one point it looks like Kimihito fell inside the giant toxic slime and his body started to melt, but it was actually a decoy puppet made of Rachnera's silk, that looked exactly like the real person (though she noted the realism was due to Suu using her own body to make the exterior of the puppet). For bonus points, Rachnera seems to be dressed as kunoichi (ninja women) usually are in fiction, fishnet top and all.
  • Nipple and Dimed: The manga freely displays nipples, but the anime won't. It usually gets by, except when Zombina purposely detaches a breast to make Kimihito pick it up, what we see is a featureless lump of flesh. This, however, is simply a case of Too Hot for TV and thus not true for the DVD version.
    • The OVA, however, not being intended for TV broadcast, really goes to town on it.
  • No Cartoon Fish: In Chapter 19, the various sea life seen in the aquarium are drawn in a very realistic art style compared to the rest of the manga.
  • No Periods, Period: Averted in Chapter 14 and Episode 6 of the anime, which revolves around Papi laying an egg, the bird equivalent to a period.
  • Nosebleed: Kimihito tends to get these, most notably the first episode of the anime when Miia bathes in his presence. It's generally in response to seeing nipples. He stops getting them fairly quickly simply due to the fact that living in a house full of attractive women with decidely limited nudity taboos who are all trying to seduce him means that he gets somewhat used to seeing bare breasts.
  • No-Sell: Satyrs are immune to the effects of the full moon, see Lunacy above for the particulars, simply because they are already horny 24/7.
  • Not Using the "Z" Word: "Liminals", or Extra Species, is the more politically correct term for Monsters in the English manga. Admittedly calling them Monsters can have very negative connotations for such a racially fragile situation.
  • Obstructive Code of Conduct: A big part of the Interspecies Protection Act is that humans are forbidden to harm monsters and vice versa under penalty of law. Naturally, this allows monster criminals to commit crimes with the local police being completely helpless to stop them. Of course, the government also authorize MON, a group of monster police officers, specifically to deal with such situations.
  • Older Than They Look:
    • Harpies tend to look like young teenagers even when fully grown for the sake of flight.. When Miia meets Papi, Miia is unaware of this, and so is rather calm at the prospect of Papi and Kimihito bathing together. Then she learns the truth.
      Miia: "I can be calm and mature because I'm a woman and she's a child."
      Ms Smith: "She's actually your age."
      Miia: (breaks down door to bathroom)
    • The various devil subspecies all look to be a particular age, even if they're actually much older.
  • Once Done, Never Forgotten: The fact that Miia has dislocated Kimihito's shoulder in Chapter 1 is brought up multiple times throughout the series. Chapter 11 has her almost drown in Mero's personal pool because her body cooled down, and she's embarrassed when the incident is brought up twice in Chapter 17, especially when Kimihito initially doubted that she could swim at all.
  • One Cast Member per Cover: A variation. The covers of early volumes have the protagonist Kimihito being featured alongside one of the Cute Monster Girls of his Unwanted Harem. Volume 1 has Kimihito with Miia, Volume 2 with Papi, Volume 3 with Centorea, Volume 4 with Meroune, Volume 5 with Suu, Volume 6 with Rachnera, and Volume 7 with Lala.
  • One-Hour Work Week: Kimihito works at an unspecified part-time job, and he somehow used his earnings to pay for the living expenses of a house of eight people, while still having enough time to participate in each chapter's wacky hijinks. Slightly justified: as the exchange program is government-sponsored, the government reimburses him for basic living expenses, as well as for refurbishing his house to accommodate for extraspecies personsnote . It's later revealed that Mero chips in with allowance received from her mother, and Rachnera makes money by selling her silk; Miia later also gets a part-time job as a shrine maiden, and Ms. Smith hired Centorea as Kimihito's personal bodyguard.
  • One-Gender Race: Lamiae, harpies, Arachnes and several others are all-female races, usually dependent on human men to reproduce (dryads are a notable exception as they can self-fertilize if need be). Many of the other races however do have males.
  • One-Note Cook:
    • While Miia is usually a Lethal Chef whose cooking is dangerous to consume, she is actually pretty good at fixing eggs.
    • Centorea is a good cook by centaur standards, but as centaurs are herbivores her cooking skills are limited mostly to raw vegetables and salads.
  • Only One Name: Most characters go under this, when they're not nameless. Exceptions are Kimihito Kurusu (mostly), Centorea Shianus, Rachnera Arachnera and Meroune Lorelei de Neptune. Also, if this piece of merchandising is canonical, Kuroko Smith.
  • Our Centaurs Are Different: While the female centaurs of this world are more like English knights of a royal Court, the males are instead modeled after the stereotypical barbarian hordes from other works. Centorea even has a full body suit of armor. They also have horse ears instead of human ears. The MonMusu Collection in Episode 3 covers centaur subspecies such as the Fragile Speedster lightweights; the large, muscular heavyweights, who're generally amiable and absent-minded; and the dairy breeds, who serve as wetnurses for other centaurs who are having difficulty with breastfeeding.
  • Our Demons Are Different: Devils resemble humans with horns, bat wings, and a tail. According to Episode 12's MonMusu Collection, subspecies are identified by how old they look (which gives no indication as to how old they actually are). Lesser devils look like children and enjoy playing pranks. Greater devils look like older human teens, and enjoy dressing in human fashions (unfortunately for them, they're often out of date) as well as playing pranks. Elder devils look like human adults, and can potentially live for centuries, resulting in them setting aside other devils' trickster ways.
  • Our Mermaids Are Different: One of the characters is a mermaid named Meroune. The MonMusu Collection in Episode 5 reveals several sub-species like sharks, former pirates whose fish bodies have a cartilage skeleton like sharks; fresh water class, a nomadic species that travels between rivers and oceans like salmon; and eels, who have long snake-like bodies that allow them to live on land and produce even more mucus than the other mermaids.note 
  • Our Monsters Are Different: The premise is about the protagonist living with different kinds of Cute Monster Girls who have both humanoid traits and quirks coming from their monster species.
  • Our Ogres Are Hungrier: The ogres in this world are horned and very large, but all of them are Gentle Giants. Episode 9's MonMusu Collection shows some sub-species, like oni, who are smaller than regular ogres, can have skin colors like red and blue, and are native to Japan; trolls, who are larger and more muscular than regular ogres; and gigantes, who are the biggest of all with heights of over 10 meters, and also the gentlest.
  • Our Zombies Are Different: The zombies of this world were created by a disease, making them effectively plague zombies, albeit benign ones. Due to their dead bodies, they can't heal injuries and are in danger of decaying unless special measures are taken. Episode 8's MonMusu Collection reveals some sub-species, like the early zombies, who were created before modern preservation technology existed, forcing them to live in cold environments to avoid decaying; the mummies, who live in deserts and require long baths to moisturize their bodies; and the jiang shi or Chinese hopping vampires, zombies from Asian countries whose stiff joints cause their arms and legs to be locked straight, so they alleviate the stiffness by practicing tai chi.
  • Out-of-Character Moment:
    • Kimihito is usually a pragmatic and humorless person, but in Chapter 39 he does crack a joke about Zombina being able to discard unwanted body parts... while being chased by a psychotic jiang-shi and carrying Zombina who has been bisected by Shiishii, the aforementioned jiang-shi! It's possible that, since the chapter is an action movie pastiche of sorts, he wanted to try what's it like to be an action hero who casually spouts cheesy one-liners.
    • In Chapter 22 and the related anime episode Manako mentions having liked the creepy and edgy message written by "D" actually Lala, full of references to death, darkness and hellfire. She never displays any Nightmare Fetishist tendencies at any point in the series. But maybe she was just envious because nobody sends her "love" letters...
  • Out of Focus:
    • Lala is often barely noticeable outside her introduction and a few focus chapters like Chapter 38. Sure, one of her traits is that she has little presence and struggles to be noticed (and let's not speak of her social anxiety...).
    • After the mothers arc, Papi has become little more than a background character until the mushroom arc, where she becomes plot important, and the vampire arc, which centers around her.
  • Out-of-Genre Experience:
    • Chapter 11 puts the harem comedy on hold for a terrorist hostage rescue. A silly terrorist hostage rescue with orcs demanding orc friendly hentai manga.
    • Chapter 38 completely skips over the typical Fanservice and downplays the comedy. The story is mostly about Lala's relationship with a terminally ill girl at the hospital.
  • Out with a Bang: The same moon that puts the girls into a mating frenzy also causes them to forget their inhuman strength and cease holding back. Kimihito, his willpower wavering, suddenly realizes exactly what that means for him if he gives in.
  • Parental Abandonment: Kurusu reveals in chapter 16 that he lives with his parents (who are currently abroad).
  • Pay Evil unto Evil: So you think you're safe from doing wrong to monster girls just because of an exploitable protection law? Kimihito and Rachnera would like to prove otherwise.
  • Pervert Revenge Mode: Zigzagged. Sometimes the girls play it straight, sometimes they're actually amused by Kimihito's Accidental Pervert moments or outright embrace them happening. When he accidentally walks in on Centorea in the shower, the next scene has him apologizing to her, sporting a nasty hoof-shaped black eye. Astonishingly for a scene like this, Centorea is ALSO apologizing: she never told him she takes a shower after her daily exercise.
  • Pillar of Light: From the opening of the anime, the harem's love manifests as a giant pillar of light that ends up forming a giant heart, which they use to hit Kimihito with their emotions. As usual, the girls go overboard and he's knocked out.
  • The Plan: In chapter 18, Kimihito and Ms. Smith go out on a "date", prompting the girls to follow them around. In the end, it wasn't really a date, but instead an attempt to flush out a potential assassin who wrote a threatening letter to him if he should marry one of the girls. Ms. Smith then plans for all of the girls to go on a date with him in an attempt to flush out the perpetrator. Although they do meet some antagonists, none of them turn out to be the one who wrote the letter. Then a second one is sent. Then they finally catch a suspicious person in chapter 22, who turns out to be Doppel, who was also the culprit for the first letter. She claims she wrote it so that he would go on a date with the girls, and hopefully pick one of them to marry, though it backfires HORRIBLY as he wound up getting closer to all 6 of his girls AND the other agents of M.O.N.. As chapter 22 ends with the culprit found, they state they didn't write that second letter... It was sent by a Dullahan named Lala who joins the house at the end of chapter 24.
  • Plant Person: There're a number of plant-based species, noted for typically not associating with other species and not wearing clothes. Dryads are one such, an easy-going species associated with small to medium-sized trees and vines, who sometimes befriend helpful members of other species. Barometz are another, a species who resemble pan fauns, but produce cotton instead of wool. Episode 11's MonMusu Collection adds two others: alraune, a flower-associated species who require other species to mate, and mandragora, a root-associated species, who are extremely shy and who can scream so loud they knock people out.
  • Planet of Hats: The various monster species usually have a personality trait or two that all of them share to some degree: harpies all have abysmal attention spans, lamia are all sex-hungry to some degree, and so on.
  • Poor Communication Kills: Essentially Chapter 28 with Papi and her mother. Papi believes her mom is trying to take her home while her mother is just trying to recover the picture she accidentally added in her message of her and Papi's father.
  • Porn Stash: The girls stumble across Kimihito's in one of the anime's omake.
  • Pretty Freeloaders: While initially played straight, but the girls gradually realizes that they couldn't rely on Kimihito everytime and have to take care of themselves. As of Chapter 43, with the exceptions of Papi and Suu, who are too mentally immature to hold a job (not to mention that Suu, as a slime girl, is an open secret and not actually covered by the interspecies exchange program), and Lala, all of the girls living at Kimihito's house have a job, are actively seeking one, or have personal wealth to make it up; even Rachnera, who gets frequent requests for her silk from various laboratories.
  • Production Throwback: Okayado's one-page comics included in the DVD sets have exactly the same style and format of his early pornographic comics, but obviously SFW and starring Kimihito and his harem instead of the eight unnamed brothers and their mates.
  • Product Placement: The Chevrolet pick-up in chapter 9, kinda...
  • Psycho Lesbian: Draco towards Miia
  • Punched Across the Room: When the two racists begin calling Miia names at the love hotel, Kimihito responds by hitting the male of the pair so hard that he's thrown into his girlfriend and they both get knocked outside.
  • Punctuated! For! Emphasis!: When Lala goes into another one of her dramatic speeches instead of telling Ms. Smith why she ran away to see Kimihito, she says:
    Ms. Smith: Why. Did. You. Come. Here?

    Tropes R to Z 
  • Raincoat of Horror: Suu's body is actually liquid, and would thus soak through any clothes she tries to wear except for a raincoat. Played With, in that this is from the Harem genre with material borrowed from the Horror genre.
  • "The Reason You Suck" Speech: Kimihito of all people gives one to Ren, a member of Rachnera's previous host family who wanted to take her back. She is berated for treating Rachnera living with her family as a trial to endure, rather than considering Rachnera's own feelings on the matter.
  • Reptiles Are Abhorrent:
    • Discussed in Chapter 26. When Miia is once again planning an evil scheme to get rid of one of her "competition", Mero and Cerea think this is why snakes have such a bad reputation.
    • In Chapter 32, she (reluctantly) takes the role of the play's antagonist named "Cobra Miia".
    • Averted in chapter 43 when Miia finds dozens of Japanese people who visit shrines believe snakes are lucky and want to get pictures with her. This even helps her get a job working there.
  • Rewatch Bonus:
  • Ridiculously Alive Undead: The zombies are a varied bunch depending on their stages of wear and tear (they rot if not preserved and can't heal, so injuries stay forever leaving them as Frankenstein-esque patchworks in extreme cases), but the 'freshest' undead are basically indistinguishable from normal humans: one of them, Yuuhi had no clue that she had died and risen again until Ms. Smith examined her and realized she had no pulse. In basically all cases of undead, they retain their human personalities, can eat, need sleep, and retain at least some measure of feeling; Zombina can't feel pain, but can feel pleasure.
  • Ridiculously Fast Construction: When Mero moves in, Kimihito's house gets rebuilt to add a new room with a huge pool in it in the span of a couple of hours, tops. Then later the house gets "expanded" (realistically it looks more like it was torn down and replaced by a larger house in the same style) over the course of a weekend.
  • Riddle of the Sphinx: One chapter focuses on a sphinx centauroid who had joined the Exchange program to test children with riddles. She does the usual "four legs/two legs/three legs" one sphynxes are known for and other ones, but the children she tells them to are Mouthy Kids who weasel their way around the riddles with logic. With some encouragement from the gang (and admitting that she really just wants to seduce smart, witty boys under the pretense of these riddles), she's eventually able to get the upper hand on the children by turning her riddles into sexual innuendo.
  • RPG Episode: Chapter 45 is a downplayed example. Kimihito returns home only to find himself into a huge dungeon, with the girls turned into characters straight out of a fantasy RPG: Centorea is a paladin, Papi a fairy, Miia a princess (later on, a shrine maiden), Rachnera a thief/merchant, Suu a giant slime and Lala as basically a more "edgy" and intimidating version of herself. It turns out that it was all a collective shared hallucination caused by the spores released by Kino, the matango (humanoid mushroom).
  • Scooby Stack: Centorea, Miia, and Papi do this in chapter 5 after Kimihito wakes up from getting hit by three tranquilizers Ms. Smith shot at him accidentally.
  • Seductive Mummy: The MonMusu Collection endcard for episode 8 of the anime describes mummies as a zombie subspecies whose native environment keeps their bodies intact and protects them from decay, resulting in them looking like attractive humans with parts of their body in bandages. The downside is that their environment robs their skin of its moisture, so they need to take long baths to replenish it, supplementing it with the placebo measure of sucking the life-force out of young men.
  • Self-Fulfilling Prophecy: When Lala first shows up, she claims to be a Grim Reaper here to pick up Kimihito, who was going to die soon. All of the girls besides Rachnera then run away from the house with him in tow. But their attempts to "save" him make things worse, such as Centorea dragging him behind her after he falls off, Meroune nearly drowning him, and Miia nearly constricting him to death again. Then Ms. Smith shows up and explains who Lala really is. Her species likes to spout off high art, difficult to comprehend things. The fact that they can detach their heads only adds to that illusion. But Ms. Smith tells them Lala isn't really much different than they are. But then in chapter 30 it's revealed that Lala actually is a Psychopomp who's pretending to be a gothy teenager pretending to be a psychopomp and she actually was attracted to Kimihito because of how regularly he was in mortal peril, yet kept willing himself back to life.
  • Serious Business:
    • Ms. Smith says the law is pretty clear that a human and non-human in the same homestay program having sex is a big no-no, and will lead to criminal charges for the human, along with the non-human being deported. (Which is pretty much what happens in Real Life.) So naturally when Kimihito accidentally takes Miia to a love hotel (because she wanted to go somewhere private where people couldn't keep gawking at her, and was also big enough to fit her), Ms. Smith leads a police SWAT team and they blow the door away into the room when they hear about a human and non-human going into a love hotel. Miia taking off her clothes and telling Kimihito to do it with her right before the cops bust in doesn't help matters any.
    • When Kimihito gets sick in chapter 13, Ms. Smith quarantines the girls from nursing him lest they catch his illness. While he only had a little cold, she explains it as if they'd waste away if they caught it (an idea that Mero finds romantic), so they send Suu to nurse him back to health, but not before giving her all sorts of weird ideas such as feeding him something strange Miia cooked up. However this could be subverted as it is clear Ms. Smith just used this as an excuse to get out of doing mountains of paperwork and falls asleep soon after arriving to "help".
    • One episode has an Ork radical group (named "PORK") pulling a "Die Hard" on an X and taking over a library... and their sole demand is that light novels and manga must start to have more Ork protagonists. The police captain is more than a little flabbergasted when he finds out.
  • Sexy Dimorphism: Centaurs, where the males are usually complete Gonks with brains to match while the females are considerably more appealing. By the time of the story, many of the females refuse to mate with the centaur males for just this reason, seeking out human males instead. The males don't take kindly to this, and developed a... somewhat "means" of getting around this, something which Centorea is desiring to escape (and for good reason).
  • "Shaggy Dog" Story:
  • Shoot the Hostage: Zombina, being undead, is not adverse to shooting through her own body to surprise kidnappers.
  • Shotgun Wedding: Miia's mom tries to force "Darling" into one.
  • Shout-Out: Numerous examples, which belong on the subpage.
  • Shown Their Work: The series often incorporates aspects of real-life animals into the biology of the monster girls, some of them pretty obscure.
    • Miia's horrible cooking and Cerea's bland dishes are both justified by real-world biology. Omnivores (like humans) have over twenty times as many taste buds as carnivores (like snakes)—of course Miia's cooking tastes fine to her. On the other hand, because herbivores, like Cerea, generally have twice as many taste buds as omnivores, omnivores just can't appreciate her vegetarian cuisine.
    • Spiders do get drunk on caffeine.
  • Shut Up, Hannibal!: Rachnera's response to the second breaking speech? Tie Lilith up and dominate her into a weak sub.
  • Sick Episode: Kimihito spends most of Chapter 13 sick in bed, with Suu taking care of him.
  • "Silly Me" Gesture:
    • Miia does this in Episode 6 of the anime after she tells everyone why she didn't taste her food before serving it to them.
    • Ms. Smith does this in Episode 7 when explaining that Rachnera "went outside without authorization" (that is, she managed to escape Ms. Smith and MON).
    • Papi does this in Episode 10 after Kimihito scolds her for having forgotten Kii.
  • Slime Girl: Humanoid slimes are a very recent discovery in this series, with Suu being the only one known. The MonMusu Collection at the end of Episode 4 reveals some subspecies, including red slimes, whose bodies are very acidic; green slimes, whose bodies are poisonous; pink slimes, who feed on nectar and smell like flowers; and black slimes, who have fallen foul of human pollution.
  • Snake People: Lamiae, like Miia. The MonMusu Collection at the end of Episode 1 lists several other subspecies, including the viper-like echidna; the medusa, whose angry glare comes from her poor eyesight; and the melusine, a shore-dwelling creature with a set of impressive but purely-vestigial wings.
  • Someone to Remember Him By: Meroune tries to invoke this when Lala says Kimihito is about to die, planning on recounting his death to their children. Miia stops her before she can get anywhere though.
  • Sophisticated as Hell: In the English translation of the manga at least, during the flashback to when humanity put a stop to the Lamia habit of keeping Tribe Husbands:
    Government Agent: Sorry, ladies. We've been turning a blind eye to it up 'till now, but you are hereby charged with kidnapping, assault, and weird, kinky crap.
  • Spider People: One of the characters is an arachne named Rachnera. The MonMusu Collection in Episode 6 covers sub-species like the small breeds, which are smaller but good jumpers like a jumping spider; the long legs breed, which have long thin legs and look and live like wolf spiders; and the large breeds, which are larger and covered with hair like a tarantula.
  • Spit Take:
    • Ms. Smith does one in chapter 5 when Kimihito blames her for the latest incident between Centorea, Miia, and Papi fighting, when she accidentally shoots him with three tranquilizers meant for the girls.
    • Cerea does this in Chapter 26 after hearing Kimihito deny Ren from being Rachnera's host family again. By doing so she sprays Miia which results in Suu attacking Miia in the background.
  • Spoiler Opening:
    • The opening shows Papi, Centorea, Suu, Meroune and Rachnera before they actually appear in the series. It also shows a quick insert of the MON squad. Interestingly, it does not show Lala.
    • Also a spoiler ending, showing all the MON girls in greater detail, revealing that they are a special monster squad, even though they're only introduced halfway through the anime.
  • Spot the Thread: In chapter 66, Yukio, the yuki-onna and propriotoer of an inn and bath house which hosts events for humans to meet liminals and become hosts for them, is studying the satisfaction surveys of her customers. She notes to Kimihito that while she has more male customers than liminals attending, both have a 100% match rate, excluding those who are kicked out for violating the rules. This shouldn't be happening and the investigation reveals the experimental filtration system she has is powered by Nega-Suu, and the water and DNA of liminals is allowing her to create humanoid slimegirls like Suu. It is these newly created slimegirls who end up with the rejected men and make them happy for the companionship.
  • Stalker with a Crush: Draco towards Miia, and "D" toward Kimihito.
  • Succubi and Incubi: Succubi are eventually introduced and prove to be as sexually aggressive as they come.
  • Suck Out the Poison:
    • In Chapter 20, a dryad Papi found (and then planted) grew into a 50-foot violent behemoth due to absorbing toxic waste. Suu absorbed the same waste and also grew huge, but managed to keep sane. Apparently, her new super-size also grew her brain, because she suggested that the best course of action would be to remove the toxin from the dryad's system. Papi immediately jumps on the dryad's giant breast and attempts to suck the toxin out...through her nipple. She is swatted away, and Kimihito is pressed onto the dryad's breast and commanded to finish the job. Awkward does not even begin to cover it. The worst part? It actually worked.
    • Chapter 44 has Centorea protecting Kimihito from the attack of an angry hornet girl. She gets stung right on the nipple for her troubles... you can see where this is going. The next chapter reveals that the venom was actually quite weak so Centorea was never actually in danger. She was just using it as an excuse to get Kimihito to touch her.
      • Lampshaded with a box on one panel that says that this technique doesn't actually work.
  • Superhuman Trafficking: The Director buys exotic monster girls and sells them into slavery.
  • Supernaturally Delicious and Nutritious: When Kimihito gets volunteered by Ms Smith to allow several blood-sucking monster girls to feed on him, they all comment on how unusually tasty his blood is.
  • Super Window Jump: Happens regularly. Luckily, the windows are made of Soft Glass.
  • Sure, Let's Go with That:
    • When Octo ends up tangled in threads after getting close to Kimihito.
      Octo: You... you set a trap for me knowing that I would go after him?!
      Rachnee: *Looks confused for a moment* That's right!
      Kimihito: What was that look just now?
    • Kimihito doesn't explain to the Melusine tribe his lack of erection is because of their overly lewd and passionate natures being a turn off. When they assume it is because of his pure heart and only having an erection for the one(s) he loves, he just asks for his clothing back.
  • Switched at Birth: In an omake featuring Miia, Centorea, and Papi's mothers together, Papi's mother explains that harpies in the same family group have an Uncanny Family Resemblance to the point of being Inexplicably Identical Individuals. Combined with harpies' birdbrained natures, mixing up one another's children actually happens a lot. Papi's mother is pretty sure Papi is actually hers.
  • The Symbiote: There's speculation that the head and body of a dullahan are two separate organisms.
  • Take a Third Option: When Lala is unsure of whether to save a dying girl's life or not, she settles on a middle ground: stealing one of Zombina's teeth and turning her into a Zombie so she can keep living after she should have died.
  • Tap on the Head: Averted in Chapter 38. Lala slams her scythe down on Kimihito's head with the specific intention of nearly killing him, so they could have a private talk in the afterlife.
  • Tempting Fate: Subverted with a vengeance in chapter 24. When confronted with his alleged fated demise and after going through too many close-calls during the chapter thanks to the girls trying to protect him, Kimihito gets fed up with the situation and stomps away while quoting every Death Flag he can think of.
    Kimihito: Miia, if... if I make it back alive, we're getting married!
    Miia: Huh... Wait, Darling! That's a Death Flag!
    Kimihito: I'm not sticking around here! I'm going home! note 
    Miia: STOOOOOOP!
    Kimihito: Can I just go to the goal right now...?
    Miia: Wait, Darling!
    Kimihito: You don't mind if I beat that thing, right?
    Miia: Of all things why do you have to raise so many Death Flags?!
    Kimihito: No problem, everything's fine. I'm not afraid of anything anymore!
  • Themed Harem: Cute Monster Girls. By chapter 4 there is a Lamia, a harpy, and a centaur, all living with one guy. It's explicitly referenced in chapter 6 by one of the girls. Chapter 8 adds a Slime girl by popular demand, and chapter 10 adds a Mermaid using the same method. Chapter 15 also adds an Arachne, and chapter 24 adds a Dullahan. As of Chapter 22, MON may well be on the way to joining them. Chapter 25 also drops hints that the Dryad girl from chapter 20 may end up in here as well, but she ultimately does not as she can't survive living outside of a forest.
  • There Is No Higher Court: Kimihito was seemingly unable or unwilling to go over Smith's head and complain to a higher authority about being forced to become a cultural exchange host.
  • They Killed Kenny Again: In hindsight, Kimihito is actually this. Lala reveals in Chapter 30 that he actually dies, but he's just too stubborn to stay dead.
  • Those Two Guys: The racist couple. For some strange reason they have a tendency to be at the same place as Kimihito and the girls who live with him at certain occasions. Yes, they do constantly spew racist insults at the girls and act like dicks around pretty much anybody they come across, humans or not. Also yes, they do have a tendency to get their just desserts in the end, not that that makes their presence any less favored in-universe.
    Kimihito: Not these jerks again...
  • Thou Shalt Not Kill Muggles: Downplayed, since there's no lethal violence in the series (largely thanks to Kimihito being Made of Iron), and unusually, the rule is present on both sides. Humans can't physically harm (or have sex with) liminals, and vice versa (though obviously this doesn't stop criminals of any species, and was the entire reason MON was formed).
  • Title Drop: At the very end of the 12th (and final) episode.
    Kimihito: It's a bit noisy and difficult at times, but every day is a lot of fun. That's everyday life with monster girls, I guess.
  • Together in Death: Lala is mostly unconcerned by the continual rivalries for Kimihito's affections, since she seems to be planning on this. As she puts it, talking to him on one of his many return trips to the afterlife, "All will die, that is destiny. Even a marriage would end when death comes... If you die, your soul belongs to me. So once you die, just leave the rest to me."
    • Back during Lala's introduction, Miia had tried to invoke this when she couldn't protest further against Kimihito being doomed to die and the girls' attempt to save him only edging toward a Self-Fulfilling Prophecy.
  • Trash of the Titans: Ms. Smith's apartment is filled with trash bags and stacks of stuff when seen in chapter 4.
  • Turn in Your Badge: Ms. Smith suspends all of MON indefinitely when she learns that one of Zombina's teeth was used to turn an ill girl into a zombie. She recommissions them when she learns that three extraspecies on the "Danger" watchlist illegally entered the country.
  • 12-Episode Anime: The anime has 12 episodes, with each episode adapting two chapters from the manga.
  • Unbuilt Trope: The series's first volume was published in 2012, just before the massive explosion of the Cute Monster Girl-centric genre. Many view the series as the Trope Codifier for many of the tropes in said genre. However, the series either Deconstructs or at least Justifies many of the common tropes in the genre.
    • Host families are biased in favor of humanoid or Little Bit Beastly species whilst predator-based species like lamias and arachnes have a much tougher time gaining trust and acceptance in the human population as their predator-based bodies cause fear among general humans.
    • Related to the above, demihumans are treated with much greater scrutiny than humans, with them having to live with a host family and being forced to obey curfews and be accompanied by their host family. Demihumans caught violating the laws can be taken away from their host family and even be deported.
    • Animal-based species are given the strength of their respective animals to match, and examined realistically as well. With the exception of Rachneranote  and Lalanote , Kimihito's monster girls frequently have trouble holding their strength back, which results in him getting injured. Should any of them not hold back any of their strength, such as during a full moon, their strength could literally kill him.
  • The Undead: Zombies, of course. Interestingly, dullahans are not, despite their detachable heads and their general demeanor revolving around death.
  • The Unmasqued World: By the time the story begins, the existence of monster girls has already become public knowledge for some time. However there are still some monster types humans are unaware of. Slimes were one of them.
  • Unmoving Plaid: The orc leader's camo jacket in episode 7.
  • Unprovoked Pervert Payback:
    • When Papi tells Kimihito she's about to lay an egg, he gets beat up by the other girls, as they assumed he had sex with her. They're relieved when they find out it's just an ordinary unfertilized egg, much like a chicken would lay. Unfortunately he's got several lumps on his head due to their beating.
    • In Chapter 39, Zombina hits Kimihito when her shirt gets torn upon over a splinter on the wooden floor while he's trying to sew her body together. She admits to herself that her newfound sense of modesty is unusual, as she had once been shameless enough to purposely remove one of her breasts and make him sew it back on.
  • Unsettling Gender-Reveal: Invoked in chapter 65. When a young man and friends are looking for Liminals to live with at Yukio's inn and bathhouse, they see three liminals being accosted by one lecherous rowdy man. The most feminine-looking of the guys sits near lecherous man and pats the man's leg with his hand under the water. The lecherous man responds in kind and touches the young man's penis, which momentarily unnerves him before the young man stands up, drops his towel thanking the man to be interested in men, while the young man's friends come from behind, all "happy" to be accepted. The lecherous man flees quickly.
  • Unusually Uninteresting Sight: When Miia catches up with Papi after she kidnaps Kimihito and drags him to take a bath with her in a park fountain, the two start getting into a brawl, and Papi claws Miia's shirt open to expose her breasts. Kimihito tells them to cut it out because they're causing a scene... only to turn to see that the gathered crowd isn't looking at them at all. It immediately occurs to Kimihito that if an entire crowd's attention is being grabbed by something, and that something isn't the topless monster girl catfight happening twenty feet away from them in the middle of a public park, then something is very, very wrong. Sure enough, Kimihito looks where they're looking, and there's a little girl stuck up a tree and in great danger of falling.
  • Unwanted Harem: Kimihito finds himself in this situation due to the increasing number of monster girls that show up and end up living with him. The fact that they fight over and seduce him constantly, and that he's not allowed to have sex with them (except the one he marries, which brings its own problems as the girls fight over that), doesn't make things any easier. Gets an extra dose of drama as he likes all of the girls and would like to marry them but is afraid to choose between them in part because, like any other caring (non-oblivious) harem protagonist, he knows that no matter who he chooses he'll still break the hearts of everyone else.
  • Viral Transformation: Zombies and vampires are the result of Humans contracting an infectious disease, turning them into one. This includes being bitten by a zombie or vampire or scratched by their teeth.
  • Weaksauce Weakness: 4/7 of the girls can't stand being in cold temperatures.
    • Suu, being made of slime, freezes solid.
    • Miia is cold-blooded, so she goes into hibernation/gets sleepy.
    • Mero's body is actually resistant to cold temperatures, but also produces liquids to keep her constantly hydrated. This means that for her, being in cold air is like the chill humans get when they go from water to air.
    • Rachnera's body slows down as well. (Similarly, she can't stand heat either.)
  • Weight Woe:
    • The profiles for some of the larger girls ("larger" referring to their overall body size, not fat) tends to keep their weight obscured.
    • The end of Chapter 59 shows that the combination of Kimhito's absence (and a corresponding lack of physical activity) and the free food provided by the Broker's company has resulted in Miia, Meroune, Centorea, and Papi having noticeably gained weight.
  • Weirdness Magnet: Discussed by Smith in Chapter 43. She asks Centorea to keep an eye on Kimihito, because she was informed that there are three very dangerous extraspecies girls on the loose, and knowing his record they will probably be interested in him one way or the other. She's right, of course.
  • Wham Episode: Chapter 22, wherein a Dullahan sneaks up behind Kimihito and apparently chops his head off. Closer inspection of the panel right before DOES reveal a notch in the scythe's blade, though. She just hooked him with it, but still...
    • Chapter 38 sees Lala befriend a dying girl, and question whether she should let her pass away or ignore the rules and save her life.
  • Wham Line
    Doppel: I didn't write a second letter.
    Lala: You. You are on the brink of death.
    Mero's Mother: Mero was taken by Octo...but she's not in harm's way, of course. Even if Meroune finds out the truth, everything will still proceed as planned. Yes...everything is going my way.
  • What Measure Is a Non-Human?: Unlike other series with similar concepts, this issue is notably unaddressed since many of the "monsters" are effectively just "Human Subspecies". The problem they face is common human prejudice akin to different minorities rather than being alien species. This is mainly because 1) they've always existed, rather than as a fantasy introduction; the human government has just kept them hidden and 2) they are effectively "human subspecies" and for the most part they act like humans with physical quirks; in fact, humans and some extra-species have always reproduced together and the zombie extra-species is, in fact, composed of actual former humans anyway.
  • Wire Fu: When Miia and Rachnera agree to help put on a show for Ils' failing shrine, Rachnera ties strands of her silk to Ils' body, allowing her to "fly" around the stage.
  • Worldof Buxom: God makes no bones about appreciating busty women, and most female characters are significantly curvy even when not spectacularly buxom. Papi, Suu (usually), Manako, and Doppel are the exceptions among the major characters.
  • World of Technicolor Hair: A downplayed case. Colors like pink, blue, lavender, green, and more are normal and common amongst the various monsterfolk, but humans retain a realistic range of natural colors like black, brown, and blonde
  • Would Hit a Girl: Kimihito won't if he absolutely can avoid it, but otherwise he will without any hesitation (directly or otherwise). When a racist couple decided to be assholes and harass Miia, he had absolutely no qualms about punching the boyfriend hard enough to send him flying into the girlfriend and send both of them crashing into the wall in a crumpled heap. Then later, when Miia and Meroune were both so insistent on winning a swimming race that it was getting risky to their health, Kimihito smacked their foreheads and firmly chided them for it.
  • Wounded Gazelle Gambit: In chapter 12, after Miia declares Kimihito off-limits to Meroune, the latter replies in kind. When he returns to the room, Mero asks him to take her back to her room because the warm air and low humidity is making it hard for her to breathe. Once they're alone, she starts asking him about not having a girlfriend, only for Miia to bring the others in wearing swimsuits to foil Mero's plan. In the end, Miia's worrying was for nothing, as Mero read about The Little Mermaid, and wants a tragic love story just like that, where she falls in love with a guy who doesn't notice her despite all of her sacrifices for his sake.
  • Your Other Left: When Miia is shedding and the last bit of the shed is by her crotch, she has to cover Kimihito's eyes to make him not see. When he is down to the last piece, he asked for directions and she told him to go right. She is referring to her right, which the author points out visually, but he assumed it's his right so he ended up inserting his finger into her vulva by accident. Neck Snap ensues.

Alternative Title(s): Living With Monster Girl, Daily Life With Monster Girl, Everyday Life With Monster Girls

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MonMusu Compilation

A frequent gag in the early part of the series.

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5 (8 votes)

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