An energetic silver-haired girl who happens to be an anthropomorphized form of the Crawling Chaos, Nyarlathotep.
The Ace: She's beautiful, athletic, intelligent, makes friends easily, is a good cook, her family's golden child, and a famous and respected space cop. If not for her flaws (namely her clinginess, playful fibbing and inability to operate at a level below "Overdrive") being so blatant, she'd easily fall into Mary You-Know-Who territory.
Anguished Declaration of Love: Declares her love for him while crying her heart out after seeing him and Cuuko being too close to each other, which causes her insecurities about his true feelings for her.
Played more literally later in the novels, where we learn that she and Cuuko would beat up their space elementary school classmate Nyogta for his bullying Hasta. Which causes a grown-up and bitter Nyogta to erase the girls from existence.
Casual Kink: Very open about her perversion, which turns Mahiro off.
Catch Phrase: "I'm the Crawling Chaos who's always creeping up on you/Mahiro-san with a smile!"
Chaos Is Evil: Played with. Like her namesake, Nyarko refers to herself as "The Crawling Chaos", but she isn't outright evil. However, she does annoy Mahiro, shows no mercy to her enemies, and has no qualms bending the rules to suit her needs.
Cool Sword: Her official list of powers include "a mechanical sword capable of cleaving dimensions"...better known as Kamen Rider OOO's Medajalibur. In the anime she only uses it in Nyarko-San W episode 9, as part of a mass of references to OOO.
Cry Cute: Usually Played for Laughs as a Running Gag every time Mahiro gives her either the snark, the cold shoulder or the fork. Then Played for Drama in Episode 6 of W, when she, unable to endure the sight of Mahiro and Cuuko acting like lovers, breaks down crying while confessing her love to Mahiro.
The Cuckoolander Was Right: Happens pretty often, much to Mahiro's annoyance. A specific example is her suggesting that Mahiro is descended from a famous deity hunter based off of his Tsundere attitude and skill with forks; Mahiro dismisses it as nonsense, but then his mother comes home and we learn that Nyarko was spot-on.
Also happens with her attempts to pick out the Chekhov's Gun that will be critical to the current case; again, Mahiro will dismiss her suggestions because they would lead to a stupid resolution, but her guesses have been right more often than his thus far.
During the "Freaky Friday" Flip plot, Nyarko even laughed with Mahiro at her own suggestion that the time-travelling rebel had stolen Yoichi's body, saying it'd be way too convenient. So of course, it turns out she was right.
Cute and Psycho: She's cute and bubbly and downright vicious in combat. She's even worse when she becomes a Magical Girl, where she sets Nightgaunts on fire and makes them puke blood while going on about "purifying naughty childrens' souls".
Cute Bruiser: Her fighting style isn't exactly sophisticated, utilizing fists, kicks or some blunt instrument.
Gone Horribly Wrong: Mahiro has her become a Magical Girl in the hopes that it'll mellow her out; it seems to work for approximately ten seconds, then she runs off to fight some Nightgaunts and acts outright Axe Crazy, as opposed to her usual Cute and Psycho merciless fighting style.
Heroic BSOD: Has a brief one when Mahiro and Cuuko have to pretend to be lovers, and he tells her to go home if she doesn't want to see them like that.
And again in the last episode of Nyarko-san W when ordered to leave Earth, but it really kicks off after Mahiro sadly says "I can't do anything to stop it". She spends the next half of the episode with Hidden Eyes and utterly silent, literally having to be dragged along by the hand by Mahiro.
Holy Hand Grenade: Nyarko uses blasphemous hand grenades. Yes, actual hand grenades (with little pink ribbons around them).
Humanoid Abomination: She claims that it's her true form, but might have just been screwing with Mahiro's head; so far we've only ever seen her as a human girl and a Henshin Hero.
Hypocritical Humor: Cuuko is a clingy unwanted love interest to Nyarko...just like Nyarko's a clingy, unwanted love interest to Mahiro. Often Nyarko will even direct insults against Cuuko that she heard from Mahiro not minutes earlier.
Mad Love: Her very clingy and stalker-y tendencies as well as her very forceful advances make her a nuisance to Mahiro more than anything and he keeps telling her to just leave him alone. He does like her deep down, but still finds her way too annoying for his tastes.
Even as a Magical Girl, she references Kamen Rider Kuuga and Dancougar; you can take the tiger out of the jungle, but you can't take the jungle out of the tiger.
The Malaproper: Happens as a result of her use of Gratuitous English; the most famous example is confusing "hate" and "(land)mine", because they're homophones in Japanese (kirai).
Manic Pixie Dream Girl: As noted elsewhere, this actually works to her disadvantage, since she's a bit too manic and clingy for Mahiro's tastes.
Master of the Mixed Message: Nyarko will gladly, eagerly, tell Mahiro that she loves him. However, in episode 7 of the second TV series, he complains that her wacky, playful nature and near-constant lying makes it so that he isn't sure she even really means it. Nyarko calmly responds that she has trouble saying it unless she's acting silly, but assures him she's completely honest. She then turns, smiles, and simply says "Mahiro, I love you."
Meido: Her "default" outfit is actually a maid outfit; it's just less obvious because of the black apron and checkerboard-patterned bow and skirt.
No Sense of Personal Space: In addition to constantly clinging to Mahiro like a barnacle, she repeatedly tries to jump him in the bathtub or the bedroom and "play Adam and Eve".
Not Cheating Unless You Get Caught: When asked by Mahiro about whether she can bring home all the manga, anime and games she bought at Akihabara, and whether this makes her Not So Different from the smugglers she's supposed to apprehend, her reply is...
Only Known by Their Nickname: When she introduces herself to Mahiro, she says "They call me Nyarlathotep, but I actually have a real name"; later novels reveal that her name is unpronouncable by human tongues, and just being able to comprehend it is a feat in and of itself, one that apparently helps you understand her better and makes you emotionally closer to her.
Ret Gone: She and Cuuko get written out of existence by their old classmate Nyogta, but get restored by Mahiro and Yithka.
Rich Idiot with No Day Job: Subverted; after she defeats Nodens, Nyarko takes 300 years' worth of paid leave in order to be with Mahiro. Soon thereafter her brother kills the gods of the Dreamlands and she receives an official reason to be on Earth, but even then the job is mostly hands-off.
Rocket Punch: In episode 11 of Nyarko-San W, she executes Kamen Rider Fourze's Rider Rocket Punch on Cuuko; the light novels outright state that she has the power to manifest "an orange rocket-like propulsion unit" on her right arm.
Rule of Cool: The light novels demonstrate that she can change into her Full Force Form with nothing but a thought; she just chooses to do Kamen Rider poses and say "Henshin!" because she's a fangirl and thinks it's awesome.
Speaks Fluent Animal: She can understand what Shantak-kun is saying without the need for a translator like Kuuko.
Spell My Name with an S: Her name is obviously supposed to be Nyarlathotep plus the Japanese suffix -ko, which is used to "feminize" a name (such as Kyo -> Kyoko). This means that Nyarko, Nyaruko, and Nyarlko are all perfectly valid spellings.
Voluntary Shape Shifter: According to the Light Novel, all Nyarlathotepians can shift their facial features at will; Nyarko uses this to prove she's an alien by making herself look like an expy of Nanoha. Additionally, she can change into her Full Force Form with just a thought.
In Episode 9, he (in Nyarko's body and voiced by Asumi) says "I'm so stupid."
In episode 12 of W, a drunken Cuune makes reference to Dream C Club, quickly adding "But I won't chose the inventor girl with the Kyoto accent!"; said character, Mio, is voiced by Eri Kitamura, serving as a nod to Cuune's hatred of Mahiro.
Adaptation Dye-Job: Has black hair in the light novels, which gained a dark brown tint in the anime.
On a similar note, his eyes went from brown in the novels to grey in the anime.
Bishōnen: Handsome enough to have smitten Nyarko just with his photo, get "scouted" for a role in an alien boys' love show (he was not pleased with this), and get confessed to by Hasta. At one point the girls tell him that he's strangely attractive to aliens.
Brutal Honesty: Tends to be very direct with his thoughts about all the Lovecraftian insanity around him. In one case, he even made Nyarko lose almost all her SAN Points by directly telling her that he doesn't like her.
Can Not Spit It Out: In episode 5 of Nyarko-san W, he mutters to himself that he'd probably be more interested in Nyarko if she wasn't so manic; he actually says this in Nyarko's presence, but refuses to repeat himself when she says "What did you say?".
Catch Phrase: He has a couple: "Wait, that makes no sense"note Literally "No, that logic is faulty.", "That was another stupid ending" and "Keep it to three lines"note Used in anticipation of Expo Speak; it's basically the Japanese equivalent of "TL;DR"
Color Failure: The poor boy is prone to this, be it for failed SAN Meter checks or having his mom returning without warning.
Crazy-Prepared: Be it forks to fend Nyarko off or a cellphone with camera with which he can blackmail her into doing her job properly. He takes this to another level in Episode 7 of Season 1, where he's got enough forks to pin Nyarko to a table for the whole night after she tried to make their "love take form".
Averted (kind of) during Mahiro and Nyarko's "Freaky Friday" Flip and Kitamura gets to "play" Nyarko.
Cry Cute: A male example (albeit in Nyarko's body) when he thought Nyarko (in his own body) died shielding him from the Star Child Guardian, admitting that he should've been far nicer to her. Of course, that was Nyarko's setup to give him a really deep French kiss.
Did You Just Get Nyarlathotep To Fall For You?: He did; he might consider it unfortunate (for now), but some fans tend to think he's an idiot for being less-than-receptive to the hot silver-haired geek girl who totally wants to play Adam and Eve.
Disappeared Dad: His father's alive and well, but he has yet to appear in either the novels or the anime. It's implied that he's stuck at work almost constantly to make up for all the honeymoons he goes on with Yoriko.
He also got Cuuko off his back by exploiting her Psycho Lesbian crush on Nyarko to win her over as a mutual ally.
He's actually developed to the point where he attempts to spot the Foreshadowing in advance, mostly by asking "What would make for the dumbest resolution?" So far he's only been right once (in episode 9 if Nyarko-San W); the rest of the time he's wrong because something comes out of nowhere and results in an ending even dumber than he anticipated.
As noted above, Mahiro's heel-dragging over his feelings for Nyarko comes from the fact that he's always afraid she'll turn out to be a malicious manipulative monster just like the Lovecraftian Nyarlathotep who's just messing with him. If he realized he was in a Lovecraft LiteRom Com and that Nyarko actually is in love with him, he'd probably be a lot happier. She is driving him insane, just not in the way he's thinking.
Non-Action Guy: Not that he can't hold himself in a fight, but when he has Eldritch Abominations chasing after him, he'd be powerless without Nyarko, Cuuko and Hasta rushing into his defense.
Not so Above It All: In episode 3 of Nyarko-San W, it turns out that he was the one carrying the mystical book that the villains wanted; he has a Big "NO!" and Nyarko complains about how mean and hypocritical it was for him to try and pin this one on her. He defends himself by saying that that's usually how it works, only for Cuuko to call him out for making excuses.
Peek-a-Bangs: Has the shy version in almost all the light novel artwork by Koin.
Ripple-Effect-Proof Memory: He has the extremely rare ability to perceive and resist shifts in the space-time continuum; this gets brought up in the first novel when dealing with Nodens and Cuuko, but becomes a Chekhov's Skill later when Nyarko and Cuuko get written out of existence and Mahiro is the only one who can save them. Considering the series' love of Kamen Rider, this may well be a Shout-Out to the concept of Singularity Points from Den-O.
Took a Level in Jerkass/Took a Level in Kindness: An odd example; comparing Nyaruani to the light novels, Mahiro comes off mellower and nicer to Nyarko, mainly because they're just single-joke shorts rather than continuous stories. Comparing the TV series to Nyaruani makes him look more hot-headed, because he has to put up with more of Nyarko and Cuuko's antics.
For a comparison, look at Remember my Love(craft-sensei) episode 11. Before (supposedly) going off to fight some powerful enemy, Nyarko hugs Mahiro tightly and asks if they can stay like that for just a minute, and if they can do this again when she returns; Mahiro's first reaction is surprise, but then he smiles softly and says "Sure." Now try to imagine the novel/TV Mahiro doing the same thing.
Tsundere: A male Type B — he's a genuinely nice and friendly guy by default, but has little to no patience with Nyarko and co.'s madcap antics. These tendencies are more prominent with Nyarko; he claims to hate Nyarko's open affection, but no matter how often he brings out the fork, he obviously finds her cute. His deredere comes out when he, in Nyarko's body, realized how willing she is to protect him even with so lithe a body, deciding that he should start being nice to her.
At the end of the first novel/episode 2 of the TV series, when Nyarko is saying goodbye and Mahiro says that he's going to miss her, she gushes "There's the dere!"
Unfazed Everyman: After a while, even Nyarue's true form doesn't really trouble him. In episode 2 of the second series, Nyarko even remarks that his tolerance for this sort of thing is pretty impressive.
We Want Our Jerk Back: In "How to Defeat a Kind Enemy", he makes Nyarko become a Magical Girl because he hopes it'll mellow her out; when this turns her outright Axe Crazy, he admits that she was better the way she was.
Creepy Monotone: Talks in a low, slow monotone, except when she talks to or about Nyarko.
Cry Cute: The memory of Xoth-731 is the only thing that can break her stoic facade and make her cry, compounded by the fact that it was she who had to destroy the entire console after it went rogue. Also Played for Laughs when she loses to Nyarko in card games.
Deadpan Snarker: Except where Nyarko is concerned, at which time she enters fangirl mode.
Defrosting Ice Queen: Starts out as just Nyarko's Psycho LesbianStalker with a Crush determined to kill Mahiro. Since Mahiro was Genre Savvy enough to exploit her Psycho Lesbian crush on Nyarko to get her off his back and even win her over as a mutual ally, she quits trying to kill Mahiro and their relationship becomes of the "like, not love" kind. She gradually warms to Mahiro thanks to his being a genuinely nice person and eventually falls for him too. Although it doesn't affect her obsession with Nyarko at all, she at least becomes willing to share her with Mahiro and comes to be a lot nicer to him.
Irony: She's living fire, and yet is a nekojita (literally "cat's tongue") — someone who can't handle hot or spicy foods.
I Want My Beloved to Be Happy: A small version occurs in episode 12 of Nyarko-san W. Cuuko, seeing how broken up Nyarko is after they're ordered to leave Earth, encourages Mahiro to be near Nyarko in the hopes of cheering her up (though Cuuko insists it's just a temporary "loan").
Mad Love: To Nyarko, she's nothing but her annoying, psychotic Stalker with a Crush, still Cuuko won't get off her back no matter what she does to keep her away from her and Cuuko is ready to kill anyone who gets Nyarko's attention.
Murder the Hypotenuse: Briefly attempted this in her first appearance when she got annoyed with Nyarko's attachment to Mahiro, which prompted Nyarko to pummel her. Nyarko never brings up to Mahiro that Cuuko tried to murder him.
NEET: She refers to her time as a "home security guard", a Japanese slang for this trope. Nyarko outright calls her a NEET a few times, as well as a Hikkikomori.
Stalker Shrine: Her room is full of pictures and figures of Nyarko and a body pillow.
Sugar and Ice Personality: Icy, unemotional and monotone at first glance, but maniacally affectionate towards those she becomes obsessed with. At first Mahiro gets the coldest ice, only Nyarko gets the sugar. The former doesn't mind, so long as they remain on cordial terms. The latter would rather get away from her. Eventually Mahiro also gets the sugar, depending on the moment he can find it annoying or cute.
Super Mode: Her Cross Fire Sequence, AKA "the battle mode where it looks like she's just wearing body paint".
Wrong Genre Savvy: In Episode 7, after Cuuko laments that no game console may replace the Xoth-731, Mahiro comforts her, telling her that someday something that can fill the void left by Xoth-731 will come her way. Cuuko thanks him, but tells him not to try setting up an Event Flag with her; Mahiro plays along.
Mahiro: "Don't worry about that. Should a flag come up, I'd break it immediately."
Yandere: Nyarko likes a guy? She will char him for good.
A young boy with long blond hair, who happens to be the humanized version of Hastur, the Unspeakable One, godde... deity of wind, depicted here more as the benign deity of shepherds than the Rapine Stormversion. He is also the son of the president of Carcosa Computer Entertainment (CCE), a famous video game developer.
The Mole: Outright tells Mahiro that he was sent by his father to gather data on Earth's entertainment from his mother Yoriko on behalf of the CCE, but decides to stay instead after the mission is called off.
Nice Guy: So sweet, cuddly and good-natured is he that it's hard to believe he is voiced by none other than Rie Kugimiya, queen ofShana Clones. This is probably the only reason he is the only member of Mahiro's harem who hasn't gotten the fork in season 1.
A green-haired woman and employee of Cthulhu Corporation, a rival video game developer to CCE (run by Hasta's father). She's also the humanized version of a Cthulhi, the star-spawn of Cthulhu himself and the closest thing to the Big C to appear in the series to date.
Humiliation Conga: Yoriko warns her that Xoth-731 is too high-end and thus too expensive for commercial release, gets a call from her CEO telling her that she (and her entire department) had been laid off, and had to watch Cuuko reluctantly destroy Xoth-731 after it caused Deep Ones to be brainwashed by a Zombie Apocalypse game currently uploaded into the system... poor lady.
Hot for Student: Becomes a teacher for Mahiro's class, and certainly acts this way towards Hasta.
Ma'am Shock: When Mahiro ran by asking for help, Luhy seemed willing to help...until the cute little girl clinging to his back called her "obaa-chan". For that, she instantly ratted the pair out to Nyarko.
And again in "How to Defeat a Kind Enemy", where Nyarko snarkily calls Luhy a 30-year-old, which causes her to ice up the room and angrily declare that even if you round her age, she's still in her 20s.
Nothing Personal: When she runs into the cast after the Xoth incident, she's quick to insist that the only reason they were enemies is because of her old job with the Cthulhu Corporation and that she wants to bury the hatchet — especially with Hasta, since she thought he was an industrial spy and was therefore harsher towards him than everyone else.
The Rival: She declares Mahiro one in the light novels after she realizes she has feelings for Hasta.
Admiring the Abomination: To an extent. While her son is somewhat freaked out and disturbed by Nyarko and Cuuko, she is more than happy to call some of their antics adorable, though she also makes it clear she will not hesitate to berate them should they cross her.
Ascended Fangirl: Just like her son, but unlike him she readily welcomes Nyarko, Cuuko and Hasta into their household.
Badass: Like her son, she has yet to lose her sanity, even openly acknowledging the existence of several Cthulhu Mythos beings. Bonus points for actually scaring the crap out of Nyarko and Cuuko at the same time using a bunch of forks.
Badass Adorable: In bright-and-sunny attitude and youthful appearance, Yoriko can easily be mistaken for for Mahiro's cute big sister.
Cuddle Bug: Frequently embraces her son upon returning from her adventures, supposedly to recharge her "sononium".
During the Trapped in TV Land episode, she pretends her personality's been "rewritten" as an excuse to be even snugglier towards Mahiro; when he says "Knock it off Mom, I know you're just faking it," she's quite disappointed.
Happily Married: At the start of the second series, she's in the middle of her 'seventeenth honeymoon. While this might seem like a cover for her monster-hunting, Yoriko confirms that her husband is fully aware of her work, and that his being so supportive is part of the reason she loves him so much (while blushing).
It Runs on Nonsensoleum: She claims that she needs to cuddle Mahiro because it produces a substance called "Sononium" ("Musukonium" in Japanese) which she needs to function properly; if she doesn't get her daily dose she becomes depressed and lethargic.
Mama Bear: Eased off on this after her initial meeting with Nyarko and Cuuko, especially after they explained themselves, but both are now conscientious enough to keep within Yoriko's good graces.
My Beloved Smother: Has minor elements of this, especially in her first appearance where she makes it very clear that she won't tolerate any untowards behavior directed at her Hiro-kun.
Noodle Incident: In the light novels, it's revealed that Yoriko has apparently crossed paths with Atlach-Nacha (Atoko) in the past, and whatever happened between them resulted in Atoko utterly despising Yoriko.
Shipper on Deck: After warming up to Nyarko, Yoriko doesn't just give her approval for her and Mahiro to date, but seems to be gently nudging them towards each other. Particularly in episode 7 of the second TV series, where she convinces Mahiro to take Nyarko on a date to apologize for his Heroic BSOD-inducing Brutal Honesty, then makes sure Cuuko and Hasta don't interfere.
Speaks Fluent Animal: She seems to be the only other character besides Nyarko that can understand what Shantak is saying.
The Ace: Episode 4 of Nyarko-San W shows him bowling three perfect games in a row, and then doing the same with 9-Ball. This is implied in the same episode as being the result of Isurugi, the yithian, sending him "happiness waves" from the distant future in an attempt to make up for possessing his body.
Gay Option: In the dating sim episode 8, it's suggested that he might confess his feelings for Mahiro if the latter fails to pick a love interest by the end of the game.
Grand Theft Me: In Episodes 9-10, courtesy of Isurugi, a rogue Yithian attempting to pull a grander version of this trope upon the rest of humanity to acquire their entertainment. He willingly leaves Yoichi after pulling off a Heel-Face Turn.
Grand Theft Me: Like all Yithians, though in his case, he wants to pull off a massive version of this trope upon humanity to obtain all their forms of entertainment. Unfortunately, his faction's boss turns out to be a SpaceMoral Guardian.
Heel-Face Turn: Upon realizing that their boss is actually using the extremists for his puritanical campaign.
A beautiful woman in a kimono who comes to Mahiro's house in Remember my Love(craft-sensei), and plays a much larger (and more sinister) role in later novels. She's also the humanized form of Atlach-Nacha, the Spinner in Darkness.
In the original Mythos, Atlach-Nacha lacked any connotation of being squicky. Thanks to a certain game, this attribute was given to the Great Old One in Japan.
Ato-ko herself first appears in Remember my Love(craft-sensei). The novels only briefly mentioned her as a certain being with a grudge against Yoriko, until her actual appearance in volume 10.
Cluster Bleep Bomb: Her discussion with Cuuko is almost totally bleeped out. Whatever was said, it embarrasses even Cuuko.
Covert Pervert: Once her gentle facade is taken off, she's quite the pervert of a level that mortifies even Cuuko.
Cuckold: In the light novels, it's revealed that her "hobby" is stealing boyfriends away from her female friends, then dumping the guy afterwards since all she cared about was the schadenfreude she got out of destroying the relationship. The more in love said couple is, the more fun Ato-ko has breaking them up...and she's set her sights on Mahiro.
Foreshadowing: Her only "appearance" in the two regular series is in Nyarko-San W episode 11, where she sent Nyarko a box of chocolates...which turn out to be laced with a Love Potion, suggesting that she's attempting to set Mahiro and Nyarko up for her inevitable boyfriend-theft attempt.
The Internet Is for Porn: She asks Mahiro to help her find a picture of a dog she saw online earlier. When Mahiro opens up her browser history, it's nothing but porn (and judging by the timestamps, she was browsing a large number of sites at the same time). For that matter, her desktop image is a salacious image of herself.
My Sensors Indicate You Want to Tap That: She can smell people's love for one another, which she uses to pick out the best moment to steal a guy from another woman. She also confirms that, despite Mahiro's fervent denial, he really does like Nyarko.
Noodle Incident: In the light novels, it's revealed that Atoko utterly despises Yoriko because of some incident in the past where they crossed paths. Thus, her pursuit of Mahiro might have a minor revenge element to it as well.
Weak, but Skilled: According to Nyarko, she's not amazingly powerful but is still a tough opponent because her attacks (webbing and poison) are hard to deal with.
Your Cheating Heart: When Ato-ko shows up in the light novels, it's revealed that she's a serial boyfriend-stealer. However, it has nothing to do with love whatsoever; she feeds on the despair that the break-up causes, and then immediately dumps the guy afterwards. Her current target is Mahiro, but she's still waiting for the best moment to strike.
Voiced by: Sayuri Hara
Another Nyarlathotepian and Nyarko's cousin. Appears in Remember my Love(craft-sensei).
Hypothetical Casting: Manta Aisora explicitly said he wanted Shimada to play Nodens; this was apparently the only specific casting choice he had in mind.
Identical Stranger: The different Nodens...es?; lampshaded in episode 12 of Nyarko-San W where the Nodens working for the PDO says that he's apparently got the kind of face that people find familiar.
Inexplicably Identical Individuals: In the last episode of Nyarko-San W, Mahiro is surprised and pissed off to find Nodens working for the PDO, but they're told there are actually multiple Nodens...ies?, and this one isn't the same as the one who tried to sell Mahiro as the star of a Boys Love show.
Though the "good" Nodens does immediately remark that Mahiro has the right look for that kind of work, and immediately gets chastized.
Kaiju: His act on a children's stage show on Episode 9, opposing Luhy as a Magical Girl.
Freudian Excuse: Blames a childhood incident where Nyarko accidentally hit him on the head during a game of space baseball for becoming Book Dumb.
Harmless Villain: In the anime, getting hit in the toe by Nyarko's motorcycle makes him A Twinkle in the Sky; subverted in the light novel, where he survives that and comes back to put up a decent fight, but still gets his ass kicked.
Childhood Marriage Promise: When they were young, she got Cuuko to say things like "I love cousin Cuune and want to marry her when I grow up" into a tape recorder; as far as she's concerned, that counts as a legally binding marriage contract.
Mad Love: Just like Cuuko with Nyarko, Cuune tends to be all over Cuuko and even though Cuuko makes it clear she doesn't want to fufill their "Childhood Marriage Promise", Cuune just won't leave her alone. Cuuko has to pretend to be engaged to Mahiro to get Cuune off her back. Cuune can't even fathom the idea that Cuuko might be in love with somebody other than her, and several times during Cuuko's "date" with Mahiro she's half-ready to attack and/or kill him.
Butt Monkey: Her attempts to meet Mahiro are always thwarted in one way or another.
Loony Fan: Of Mahiro's; every time she appears, she's plotting out the order in which she's going to shake his hand, get an interview, have him autograph her doujin, etc. It never once occurs to her that he might not enjoy being the "star" of a Boys Love comic...
Moe Anthropomorphism: Of Ut'ulls-Hr'ehr, one of the Great Old Ones; one Japanese pronunciation of the name is "Uutsuru Heea" (ウーツル＝ヘーア), from which "Tsuruko" comes.
Otaku Surrogate: She is obsessed with manga to the point of living on Earth and creating some herself.
Ship Tease: With Yoichi, who runs into her at least twice. The first time time is a Not What It Looks Like moment in episode 4 of season 2 caused by Isurugi, the second in episode 11 with him being under the influence of a Love Potion.
Yaoi Fan Girl: She is the artist for a yaoi doujinshi featuring Mahiro.