Manga / Arachnid

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From bottom to top: Alice Fujii, Gokiburi and Yoriko Tajima

A manga done by author Murata Shinya and artist Shinsen Ifuji since 2009 and published on Gangan JOKER, Arachnid provides an unusual take on the standard shonen Fighting Series, with an interestingly deranged cast and a wide variety of exotic fighting styles.

Alice Fujii does not have a fun life. She's spent the last few years being tormented and abused by her drunken uncle, whilst her unusual mental disorder and dearth of social skills have led to poor grades and a complete lack of friends at school. Then a mysterious assassin kills her uncle, press-gangs her as his apprentice, and subjects her to Training from Hell for a few weeks before trying to kill her when her recruitment application falls through. Now she's got an ever-increasing price on her head as she fends off one murderous, arthropod-themed lunatic after another, and the only allies she can turn to are the slightly less murderous arthropod-themed lunatics.

There's also a spinoff prequel named Caterpillar, which focuses on an assassin named Imomushi who had her own troubles within the Organization a year before Alice became involved.

The main series has ended on December 2015 at 72 chapters. It has been licensed in France by Soleil Productions since April 2015. Not to be confused with the 2001 spanish horror film Arachnid. Also, for Murata's other takes on people fighting with animal abilities, see Jackals, Vaia'n Maiden and Killing Bites (anything from him other than Majo ni Ataeru Tettsui, really). Yū Sasuga's Terrafor MARS also deals with this concept.

Arachnid and Caterpillar contain examples of:

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    General 
  • Action Girl: Alice and virtually any other female assassin.
  • Aerith and Bob: On one hand "Alice" is a foreign name that her teachers have trouble pronouncing. On the other, the rest of the cast are a bunch of people with fake names and who are codenamed after insects.
  • Always a Bigger Fish:
    • The narrative exposition on paraponera clavata ants (aka bullet ants) in Caterpillar states they're so danguerous a group of army ants would avoid fighting a single one of them. The exposition on dinoponera ants in Arachnid is practically copy-pasted, except the paraponeras are the ones fleeing.
    • Dinoponera herself is played up as so dangerous she could kill everyone on her own. In practice she ends up as little more than a nuisance whom Alice surpasses very hard. Then Sasori ambushes and makes short work of her.
  • Animal Motifs: ...or rather, an insect motif, each for every assassin. However, given Alice and Imomushi are protagonists, those two get a handful of different spider and caterpillar species motifs for the sake of versatility.
  • All Men Are Perverts: In combination with All Men Are Rapists: With or without the Queen's Rule brainwashing, few men in the story aren't always harassing women and trying to rape them.
  • All Men Are Rapists: In combination with All Men Are Perverts: With or without the Queen's Rule brainwashing, few men in the story aren't always harassing women and trying to rape them.
  • Almighty Janitor:
    • Shidemushi seems to be one, but he's never shown in a fight.
    • Suzumebachi worked as a mailman before he got promoted to front man of the Organization.
    • Osamushi and Kagimushi work as mangakas. To be specific, they're expies of Osamu Tezuka and Shotaro Ishinomori.
  • Assassin Outclassin':
    • A bunch of assassins are called to kill Alice for a reward, but they all fail and even fight amongst themselves because the reward increases with every assassin killed. What makes it a less than bright idea is that the target is a Crazy-Prepared Trap Master who's familiar with the place the hunt is set in and she even got some days of prep time for the event because Sasori babbled about it to her before.
    • Same goes for Imomushi in the prequel, who isn't very worried about being on a ship full of people trying to kill her.
  • Attempted Rape:
    • Alice from her uncle in the very first chapter, and then Oki from Hibiki's thugs in Chapter 12. The trope eventually escalates to absurd levels, with the entire student body of Alice's school being brainwashed into raping people and turning the whole country into a massive orgy.
    • Hanakamakiri is the Designated Victim of rape attempts in the prequel.
  • Author Appeal: Arachnid is Murata's second manga about people with Animal Motifs, this time focusing entirely on arthropods. Once or twice per chapter the narrator prattles on about the qualities of bugs and at one point explains that the Organization doesn't actually force its assassins to use a bug motif, but they all do it anyway out of a fascination for those creatures.
  • Barbie Doll Anatomy: Played straight in Arachnid, but thanks to its seinen perks Caterpillar has detailed breasts.
  • Beware My Stinger Tail: Sasori turns out to have a long mechanical scorpion tail attached to her back. How she hides that, especially in the outfit she wears in the prequel, is anyone's guess.
  • Big Bad:
    • "Army Ant" Sara Kurokawa claims she's the boss of the Organization. But she is a decoy who follows Kuramoto's orders. And Kuramoto isn't the boss either. Yoriko is.
    • "Swallowtail Butterfly" Yanagi Akiho fills this role in the prequel. But actually it's Imomushi's own sister Mika posing as Yanagi.
  • Blade Below the Shoulder: Dinoponera has extendable needles inside her gauntlets, which have the immensely painful effect of her namesake's sting. Paraponera and Suzumebachi also use this weapon type.
  • Blade on a Stick: Kabutomushi wields a halberd with enough strength to shove people far away and make craters on the ground.
  • Bland-Name Product: Kahen Rider. i.e., Transforming Rider instead of Masked Rider. Later on, Sailor-Force is shown.
  • Boss Subtitles: Used in Caterpillar to introduce each character and their rank. Arachnid also does it late on the plot with characters who hadn't been seen in a while.
  • Bottomless Magazines: The Kumoito used by Kumo and Alice has an untold length of special spider thread inside it. It is later explained that the thing is actually a Living Weapon and produces string for as long as it is cared for.
  • Bowdlerise:
  • Breather Episode:
    • Chapter 17 in Arachnid, discounting all the sexual harassment on Kuramoto in the end, is about Alice, Yoriko and Gokiburi peacefully hanging out on a mall some days before the battle royale begins.
    • After chapter 50 ended with a character getting gang-raped offscreen, 51 and 52 are nearly all slapstick comedy.
    • Every once in a while there's a chapter in Caterpillar that takes place during the period Imomushi and Hanakamakiri were getting to know each other.
  • The Brute: "Sia ferox" Riock, who just recklessly throws Megaton Punch after megaton punch. It's a bit of a Running Gag for him to get countered and easily defeated but he never learns.
  • Butt-Monkey:
    • After an imposing introduction, Hibiki becomes a subject of comic relief as not only Dinoponera repeatedly humiliates and beats him silly, but he's also a victim of his own Dynamic Entry gag and is kicked into a hole. Then the guy actually gets zombified offscreen.
    • Riock has an expanded role in the prequel, but all it amounts to is trying and immediately failing to punch people.
    • Most of Oki's screen time in the prequel is spent on the background looking stupid.
    • Also in the prequel, Dorcus' three partners also spend all their time just looking stupid in the background and are defeated in all of 5 seconds once they do take their chances at fighting Kabutomushi.
  • Carnival of Killers: The "Arachnid Hunt" in the main story sets a prize on Alice's head that increases every time one of the participating assassins is killed. In the prequel, Imomushi is also the target of one. The people attacking her carry a series of envelopes with details on how her sister Mika was killed and rich people are betting on the outcome of the fights.
  • Catch-Phrase:
    • Alice's "I have no choice but to kill" when she or her friends are in grave danger.
    • Oki's excited "It's great to be hated!" when she's having fun humiliating people like a dominatrix.
    • Sasori's "A scorpion has three friends" pre-torture speech.
    • Dinoponera's "If it's you, maybe you can become my friend" when she has good expectations about her opponents. She's also prone to muttering "mai mi thang!" ("no way!" in thai) over and over when panicking.
  • Charles Atlas Superpower: Everybody in this series is a "perfectly ordinary" human. You may need to remind yourself of this repeatedly.
  • Chekhov's Gag:
    • A minor one. When Alice is feeling bad about being all hurt and bandaged up with an eyepatch, Yoriko and Oki tell her she looks stylish and cute. Sara was introduced at around the same time, and much later it turns out she's pretty much wearing her eyepatch for the sake of fashion.
    • In Kabutomushi's first two battles, Yoriko gets knocked down on her back when Kabuto sends Jigabachi through a wall and falls down a floor when Kabuto destroys the ground below them. Yoriko repeatedly says she thought she was going to die, but Kabutomushi assures her she won't... die just from falling from 3 meters. Kabutomushi herself is who kills Yoriko at the end of the story, by blowing her off the school's rooftop.
  • Chekhov's Skill:
    • Oki is able to secrete oil as an evasion ability. Later Kabutomushi explains she taught her to subtly do it when in trouble to leave a trail behind her for Kabuto to follow. It happens even though Oki was brainwashed at the time.
    • Alice once secretly uses her thread to put a leash on Oki's neck, so she can listen to her conversation with Hibiki from afar and come to her protection if she fails to negotiate with him. Much later, Alice impressively uses this technique to foil a villain's plans and crush their neck.
  • Chekhov's Gun:
    • Kabutomushi mentions a "Hercules Horn" weapon at one point in Arachnid. This never comes into play and is left for Caterpillar instead.
  • Cheshire Cat Grin: Sasori's default expression.
  • Child Soldier: Some characters are shown to have been trained by the Organization since they were small. Among them, Dinoponera was the one doing mercenary work in war zones as soon as she was able to carry a gun.
  • Crazy-Prepared:
    • Alice to ever greater lenghts, courtesy of her Disability Superpower which is very befitting for a spider-themed string user.
    • Amenbo knows how to inflate like a balloon to avoid drowning. You read that right.
    • Kabutomushi can survive even seemingly lethal attacks to the heart thanks to her implanted exoskeleton armor.
    • Being an experienced mercenary, Paraponera gives Imomushi a lot of trouble.
    • Dinoponera's "Concentration Driving Force" ability gives her heightened senses comparable to Alice's. And while it is mentioned Alice's senses can't save her from sufficiently fast attacks, Dinoponera is agile enough to avoid practically anything. This ends up subverted, though, when it's shown Dinoponera is actually really short-sighted when making plans.
  • Creepy Centipedes: "Caterpillar" Imomushi, "Centipede" Mudake and "House Centipede" Geji.
  • Creepy Cockroach: Oki is a pervert and has this weird ability to make her skin all slimy.
  • Cute and Psycho: Nearly every girl in the series.
  • Cute Bruiser: Oki, Kabutomushi, Geji and Dinoponera. Alice has her moments, but she mostly uses string tricks to fight.
  • Dark-Skinned Blond: Riock and Dinoponera.
  • Death Seeker: Kumo trains Alice so she could kill him. In the prequel he's shown to not have cared much for his own life for a long time, though he wasn't letting himself go down without a fight.
  • Defeat Equals Friendship:
    • Oki is brought along by Alice after being defeated and becomes her most trustworthy friend. It helps that Oki turned out to not have kidnapped Yori and just wanted to make Alice her slave instead of killing her.
    • In the prequel, Riock is shocked when Imomushi beats him in a fist fight and pledges his loyalty to her.
    • Dinoponera claims she's looking for strong people to fight and befriend. In reality she doesn't know when to stop beating people and is hardly impressed no matter how much they manage to survive her. And so this never works out.
  • Depopulation Bomb: The Organization has population control as their main objective.
    • It the backstory, it is shown that the atomic bombings of Hiroshima and Nagasaki were actually done as a secret agreement between the United States and Japan. The USA would get to show off before Russia and Japan would deliberately off a chunk of their population.
    • In the story proper, they manage to get countless people killed by causing a Zombie Apocalypse in Japan.
  • Disability Superpower: Alice's "Congenital Excessive Concentration", which causes her to single-mindedly concentrate on the most inconvenient things. With training, though, it allows her to enter a kind of hyper-aware state and formulate battle strategies in seconds, and serves as arguably her greatest weapon.
  • Disney Villain Death: Seems to be Kabutomushi's favorite way of dispatching enemies, what with her beetle and spear theme and all.
  • The Dragon:
    • Suzumebachi to the Organization boss. A number of people have held that title in the past.
    • Sara to Kuramoto.
    • Paraponera and Ground Beetle to Ageha.
  • Enfant Terrible:
    • Digger Wasp, a boy who wants to brainwash girls and put them on dominatrix outfits.
    • The Weaver Ant triplets in the prequel, who try to force women to "play doctor" with them.
  • Explaining Your Power to the Enemy: Not only the assassins do it, but then the narrator also lectures us on how their powers relate to their insect motifs, not that it helps make much sense of the supernatural ones. Sasori has this routine in which she paralyzes people and then explains what she did and how much she's going to enjoy slowly killing them. It's also been inverted once, when Alice figures out how Dinoponera is able to concentrate harder than her and then explains to Dinoponera the differences between their methods.
  • Expy:
    • Shinya Murata's Jackals already had a spider-themed assassin with a Razor Floss weapon in Turis Spider, who aside from being blonde and older than Alice looks similar to her, down to having the same height and weight.
    • Geji is pretty much the cute and cool assassin Tomoko Kuroki would daydream of being. The extra content of volume 8 freely admits this with a parody chapter focusing on the traits they share and a sketch of Geji by the author which is literally Tomoko.
  • Fanservice: Female characters are shown in various states of undress constantly, and are put into compromising positions with each other practically once a chapter. Caterpillar takes it one step further by actually including uncensored nudity. The fanservice in both series borders on Squick very frequently, however, as it tends to be accompanied by (either attempted or successful) rape.
  • Flash Step: The faster characters frequently appear out of nowhere behind each other. And they usually look away from the target, just to look cool. They do have insect motifs, after all. It's later exaggerated in chapter 48, in which Alice practically teleports around Dinoponera, who insists in trying to hit Alice from behind.
  • Guns Are Worthless: Some characters do use guns, but hardly get any use out of them and soon completely forget they exist as focus is shifted to the assassins' weird insect-themed abilities and weapons. One exception is Ginyanma, who wields a sniper rifle. How would Alice even deal with a sniper? By hurling her knife and thinking really, really hard so it flies through all the miles to Ginyanma and pierces through her scope and head, that's how.
  • Hair Antennae: Oki, as part of her cockroach theme. They even move while detecting movements around her. Oddly enough, she spontaneously gained those antennae just by identifying with a cockroach she saw back when she was an abandoned baby in a thrashed house.
  • Hammerspace: Kabutomushi hides her Kabuto Horn halberd folded in half under her shirt, but it's still far too big for it to make much sense. Then there's Geji who hits Oki with a heavy filled sock that she was still wearing on the previous page. And also Sasori, who hides a scorpion tail larger than herself under her coat. Hanakamakiri often pulls her scythes from out of nowhere, too.
  • Heel–Face Turn:
    • 'Cockroach' Oki, the Psycho Lesbian assassin, would be the most obvious example (and overlaps somewhat with High-Heel–Face Turn), though Yoriko, the Alpha Bitch who befriends Alice after the latter saves her life, serves as a less extreme case.
    • In the prequel, both Riock and Kumo end up fighting on Imomushi's side.
  • Hot Springs Episode: The Febuary 2015 crossover between Arachnid, Caterpillar and Killing Bites.
  • I Know Mortal Kombat: Hibiki based his fighting style on the "Kahen Rider" series, training until he made reliable techniques out of the show's ideas. Riock, on the other hand, took from that show an idea of surviving through brute force alone.
  • Idiosyncratic Episode Naming: Both Arachnid and Caterpillar are One Word Titles, and named after animals.
  • Improbably Female Cast: The Organization sure does have a lot of high school girls under its employ... Played with somewhat, as while there are a decent number of male characters, only a very small few of them manage to stick around after their debut fights and receive any real characterization.
  • Improbable Weapon User: If an Organization assassin uses a weapon, it'll be an extremely weird one. Alice's Weapon of Choice, for instance, is the "Kumoito", or "Spider's Thread", a length of spider-silk with a hooked blade on the end that works rather like a cross between Razor Floss and a Grappling-Hook Pistol.
  • Instant Expert: The defining trait of Congenital Excessive Concentration is not the "time-stopping" concentration, but this trope instead. Alice learned all the assassination skills Kumo ever knew in only two weeks.
  • Japanese Beetle Brothers: Kabutomushi is a girly, intense and incredibly strong rhino beetle lady. Caterpillar also has four Stag Beetle-themed people trying to pick on her.
  • Kick the Dog:
    • Rape attempts for the heck of it cover over half of the series' antagonists. Even a guy like Hibiki who is a justice-obsessed Knight Templar and who emulates a guy who wouldn't rape or brutalize his victims attempts to get Oki and Alice raped.
    • Dinoponera kills a poor employee of Alice's school for no reason when she greets Kabutomushi, showing that for all of her talk of wanting friends, she's an unreasonable bitch who feels contempt for normal people. She's also excessively cruel to Alice when she discovers the spider girl's cheesy Instant Expert skills.
  • Lantern Jaw of Justice: "House Cricket" Hibiki and "Sia ferox" Riock.
  • Late-Arrival Spoiler:
    • The cover for Volume 11 depicts Sasori with her surprise scorpion tail. Volume 12's cover heavily hints at a big plot twist, but at least it had already been revealed in the end of the previous volume.
    • Chapter 59 of Caterpillar, first released while Arachnid was nearing its end, spoils the major plot twist of Yoriko being the Organization boss, though it doesn't refer to her by name or explain how she came to be this way.
  • Little Miss Badass: Alice, Oki, Kabutomushi, Geji, Dinoponera, Hanakamakiri and also Imomushi in her childhood.
  • Mad Scientist: Jigabachi, who installed the mechanical tail on Sasori.
  • Make Me Wanna Shout:
    • While bored from fighting Hibiki, Dinoponera suddenly stuns everyone in the corridor with a loud scream. She does it again later to escape after being defeated by Alice, but Kabutomushi isn't affected and almost crushes her.
    • Her father Paraponera also pulls this off against Kumo to distract and shoot him dead.
  • Male Gaze: Lots of it.
  • Mercy Kill:
    • Alice does this to Kumo after she's forced to fatally wound him.
    • Caterpillar finds Paraponera's raping one of his targets and shoots her dead from out of pity.
  • My Kung-Fu Is Stronger Than Yours: Or rather, "my bug motif is better than yours". Battles will always have the narrator describing the qualities of the antagonist's bug motif while Alice's having a bad time, and this is followed by her triumphant counter attack being compared to a certain spider species that preys on the antagonist's bug.
    • When it turns out Alice and Dinoponera have similar abilities, Alice's victory comes from analyzing how Dinoponera works up her focus and not only copying it, but also instantly improving on it.
  • No Celebrities Were Harmed: Two high-ranked assassins based on Osamu Tezuka and Shotaro Ishinomori are introduced in the prequel.
  • One-Word Title: Arachnid and Caterpillar are the names of entries in the series.
  • Older Than She Looks:
    • Kabutomushi is said to be an adult in a teen's body. How and why she's like this isn't explained, but it might have something to do with her cyborg-esque enhancements.
    • Once Yoriko reveals herself as the boss, she claims she's over a hundred years old.
    • Osamushi got rejuvenated at some point after he retired from the manga industry and disappeared.
  • Orwellian Retcon:
    • When Dinoponera first appears, she's walking around with a stern look while Sara freaks out about how dangerous she supposedly is. She greets Imomushi with a similarly deadpan expression, but that was changed to a smug smirk in the volume print seemingly to make the transition from what she looked like to her psycho-Genki Girl personality less jarring. One can wonder if they didn't actually decide to pull a 180º change on her character at the last minute, given even her early artwork was pointing to her being no-nonsense.
    • As previously mentioned, the volume prints censored a gory murder scene and removed swastikas from scenes where nazis are mentioned. There's some other minor art changes and at least one modified line in there too. Ginyanma's bullets, for instance, originally looked organic but were redrawn to look technological instead.
  • It's Personal with the Dragon:
    • Alice believes she can make the Organization collapse if she kills Suzumebachi, who turns out to be her own father.
    • Paraponera earns this relationship with Imomushi in the prequel when he fatally injures her sister Mika while Imomushi was trying to make peace with her.
  • Posthumous Character:
    • Kumo dies early on the main story, but his lessons and commentary on some characters' abilities is remembered by those who knew him.
    • Alice's mother and Imomushi's sister, whose deaths motivate them.
  • Professional Killer: The insect-themed assassins. For a given value of "professional", anyway.
  • Psycho Lesbian: Gokiburi sets a standard when she tries to make Alice her slave and have her crawl naked around the school. While she softens up from becoming good friends with Alice, villainesses Army Ant Queen and Ageha go much further with the trope.
  • Rape Is a Special Kind of Evil: A lot of the bug assassins cement themselves as evil by attempting to rape someone or get them raped by someone else. They are also the ones most likely to fall victim to some Cruel and Unusual Death later.
  • It Runs on Nonsensoleum: Other than Kabutomushi and her implanted armor, most of the characters don't seem enhanced. But even when their tricks are just plain supernatural, they're able to do them because they somehow fit in their insect motif, without any further explanations other than "they did special training".
  • Scary Scorpions: Sasori revels in paralyzing and torturing people to death with her poisons.
  • Serious Business:
    • Somehow, this Organization of hardened assassins ended up all bug themed because they all simply like bugs. One character even claims that determining which insect is the strongest is mankind's greatest question, though we never quite see if the entire world really is like that.
    • Hibiki and Riock fighting over who is best fit to be a real-life Tokusatsu hero. That the in-universe equivalent of Shotaro Ishinomori is a bug assassin and Imomushi's master does give them validation.
  • Shameless Fanservice Girl
    • Geji gets her clothes stolen by Goki but oddly enough never complains or anything.
    • Imomushi has a few scenes in the prequel where she ends up fighting or casually walking around while nude.
    • Also in the prequel, Bokugehamushi has the power to grow long spikes all over her body and wears nothing but a robe because of it. She goes on to glomp Riock's head to point-blank him.
  • Shout-Out:
  • Skyward Scream:
    • Alice after she kills Kumo.
    • Imomushi screams for three pages and a half after her sister dies for real.
  • Smug Smiler: A frequent expression on female antagonists such as Sasori, Geji and Dinoponera.
  • Smug Super: Each insect assassin is more arrogant than the last. They also tend to get messed up very badly by Alice, who herself has done epic boasts on how spiders are the pinnacle of arthropodkind.
  • Somewhere, an Entomologist Is Crying: The series greatly exaggerates insect qualities for the sake of justifying the superpowers of the assassins. And unlike how all the enemies are based on a specific species, Alice jumps all over the place when analogies are made. One chapter she's an Araenid, the next she's a Salticid.
  • Spiders Are Scary: Alice normally is a gentle and kind girl, but in battle she becomes much colder and creepier.
  • Strong Ants: Some antagonists are ant-themed and have some of the associated quirks.
    • "Army Ant" Sara is helpless in battle but turns the entire student body of her school into her brainwashed minions.
    • Dinoponera comes equipped with poisoned stings and is shown to be greatly strong, fast and resistent.
    • Dinoponera's foster father, Paraponera (Bullet Ant), had many of the same abilities as her and was tough enough to survive a grenade exploding on his face.
    • The Weaver Ant triplets have abnormally high strength and a device on their palms that lets them easily hold anything over their heads.
  • The Syndicate: The nameless Organization, which targets people they deem worthless to take over their identities and commodities. Their main purpose, however, is to regulate the world's population. They also pick people who have nothing to live for and turn them into cold-blooded assassins with bug motifs. And of course, they have much control over the world and are untraceable.
  • The Ugly Guy's Hot Daughter: Dinoponera to Bullet Ant, but she's adopted.
  • Un-person: The Organization owns all records of their members' existances and will erase those if they die. Alice refuses to join them to avoid being subjected to this.
  • Used to Be a Sweet Kid: A sizable number of the villainous bug nutjobs get a miserable backstory to explain why they had to work for the Organization to keep living, but on occasion it turns out they were sadists even as children.
  • Webcomic Time:
    • Arachnid had 54 out of 72 monthly chapters take place over the course of a single afternoon.
    • Flashback breather chapters aside, Caterpillar also takes place in a single setting over the course of a single day, and is also several chapters longer than Arachnid.
  • The Worf Barrage:
    • Alice often pounces at her enemies like a salticidae spider, but beyond ripping off a chunk of Kumo's neck at the beginning, she always gets knocked away before she can do any harm.
    • Any attempts by Kabutomushi and Hibiki to harm Dinoponera. She dodges through her Kabuto Slide and either blocks or completely shrugs off his Rider Kicks.
    • Every time Riock tries to punch somebody in the prequel, he gets either blocked or countered and then is knocked out silly in one move.
  • The Worf Effect: Tough characters are frequently introduced only to get easily beaten up or even killed by the next in line, who then also gets schooled by another person.
    • Oki claims she's the fastest among the assassins, yet gets easily beaten when someone turns out to be more danguerous than her. Kabutomushi and Imomushi, as strong as they are, can't harm Dinoponera at all. Dinoponera goes on to casually slap around some other assassins only to also fall victim to this trope when she meets Sasori.
    • This trope is really all Riock is used for in the prequel.

    Arachnid 
  • A Birthday, Not a Break: Alice's mother died on Alice's birthday, just after promising to take her to a theme park sometime.
  • Abnormal Ammo: One of the assassins is a sniper named Gin Yanma. She sits hidden on some building and kills people from afar. Seems simple enough, but then it turns out her bullets have dragonfly wings for them to travel farther and faster.
  • Aborted Arc: Imomushi comes to Alice's school to question Suzumebachi about her sister's death, implying he's still hiding something important about that from her. Nothing comes out of this in Arachnid proper because not only Imomushi gets more or less killed (or was she?) with little fanfare and isn't mentioned again, but Suzumebachi is also killed later.
  • Academy of Adventure: A polite way to describe Alice's school. A less polite (though somewhat more accurate) description would be 'death-trap crawling with murderous psychos', from the students to the teachers. Even the Organization Boss is lurking there somewhere and there's a huge incinerator for body disposal. Despite coming to realize how dangerous her school is, Alice still finds herself going there because she has nowhere else to go.
    Alice: "You said that... you'd negotiate with the Organization... Specifically, where would we go to? And who should we speak with?"
    Oki: "School."
  • Archnemesis Dad: The front-man of the Organization, Suzumebachi, is revealed to be Alice's father.
  • Armor-Piercing Question:
    • Yoriko asks Alice if she, a kind person who wasn't able to kill a bully like her, could really be a murderer. Alice had killed two people in self-defense by then, but lies to preserve their friendship. She feels guilty about it and eventually confesses the truth to Yoriko.
    • To break Alice's guard, Imomushi suddenly asks her if she's a virgin. In the background, Amenbo and Riock look like they're actually waiting for an answer.
  • And the Adventure Continues: The story ends with Alice facing the rape zombie apocalypse that's overtaking Japan. Kabutomushi and Oki are also travelling on their own through the urban wastelands.
  • Armor-Piercing Response:
    • When Kuramoto is talking to Alice about her issues with bullying, Alice insists her troubles are no big deal when compared to people who have it worse. Although she seems to disagree with Alice's reasoning, Kuramoto still protects Alice from being raped, at her own expense, while saying the same. The truth is that she deeply resented Alice for being so forgiving to people who have mistreated her.
    • Dinoponera asks Alice about how her upbringing was like and if she fought in any wars. Alice and Kabutomushi reply she's a plain schoolgirl who's been trained for less than a month. Dinoponera flips out at this, angry that Alice could attain her skills so quickly just because of some ability she was born with.
    • Alice finally admits to Yoriko that she is a murderer, but Yoriko doesn't think that's an issue after all. Alice is so overjoyed that she completely misses Sasori spawing into the room and killing Yoriko right after.
  • Asshole Victim:
    • Yoshio, Alice's abusive uncle in the beginning. Given how Kumo's murder of Yoshio prevented him from raping her, Alice is practically thankful to Kumo for it.
    • Mudake is introduced while surrounded by unconscious girls he's heavily implied to have raped. He's caught by Sasori and presumably given a gory offscreen death.
  • Badass Creed: Alice has a "kill or be killed" motto.
  • Batter Up!: In chapter 12, some of the people working for Hibiki are holding Nail Bats. It's rather amusing that one of them has a Nail Golf Club. Even more amusing when Alice swings it at his face.
  • Big Bad Friend: Kuramoto is responsible for the school-wide orgy during the Arachnid Hunt and Yoriko is behind everything.
  • Bittersweet Ending: Alice survives the Arachnid Hunt and solves all the mysteries regarding her past, but to her dismay, Yoriko was in charge of it all and was killed by Kabutomushi. The Organization is still out there and they succeeded in bringing ruin to Japan through a zombie apocalypse. Most of the named characters are either missing or zombified and Alice has to fight on her own, having lost Kumoito and parted ways with Oki.
  • Blade Run: Dinoponera sits on Kabutomushi's halberd when Kabuto first tries to attack her, then hangs on it to avoid being smashed into the ceiling. Later she also walks on the halberd's pole, too.
  • Blatant Lies: A teacher demands to know what Kabutomushi's massive spearlike weapon is. Having used it to shove two people out of the building, she tries to claim it's a mop.
  • Blunt "Yes": Hibiki says this when Alice asks if he had a "deep relationship" with Kumo. Oki then bluntly asks if he is gay. He confirms it again but then he backpedals.
  • Bolivian Army Ending: The story ends with Alice surrounded by the zombie hordes that destroyed Japan and about to charge against them.
  • Bookends:
    • Near the end, Alice confronts her biological father, Suzumebachi, in a rooftop, much like how she had to fight her parental substitute Kumo in the beginning. Ginyanma even watches over both fights.
    • The story begins with Alice's uncle trying to rape her and ends with a horde of sex zombies after her unmentionables.
    • One of the poster collectibles that came with volume 14 was a redraw of the cover page from chapter 1.
  • Brainwashed and Crazy:
    • At one point Oki is controlled by a device from Digger Wasp, who gives her a dominatrix outfit and has her believe he is Alice. Oki's colorful personality actually isn't affected, but she doesn't notice how unusual "Alice's" orders (such as torturing her friend Yoriko) are even when Digger Wasp is detailing the effects of his mind control right in front of her.
    • Meanwhile, Sara leads and spreads mindless zombie-like students around for them to overpower and rape her enemies. Kuramoto turns out to be the one responsible. Through exchange of bodily fluids, she can spread a virus that places the infected under her will. Sara retains her consciousness because she's been given a role by Kuramoto, but after Kuramoto is killed both Sara and everyone else appears to go brain dead permanently.
    • Yoriko has the flat-out supernatural ability to brainwash people. And for as long as she's perfectly in control of her Suzumebachi enforcers, she somehow remains ageless.
  • Brick Joke: When asked by a shocked teacher what she is doing with a large spear, Kabutomushi claims it is a mop. Later, Yoriko is seen fending off the zombiefied student mob by swinging an actual mop at them.
  • The Bully: Yoriko is terribly cruel to Alice in the early chapters, to the point Alice considers killing her, but after the first encounter with Sasori, Yoriko has to keep Alice with her for protection and the two begin to get along.
  • But Now I Must Go: After the Arachnid Hunt is over and Japan is being ruined by the nation-wide orgy, Alice leaves Oki to fight off the zombie apocalypse and take down the Organization for good.
  • Car Cushion: When Abu gets defeated by Kabutomushi, he's shoved out of the building and falls right on top of a nearby car.
  • Cerebus Rollercoaster: The manga has a very grim start, what with poor Alice almost getting raped by her uncle, staring death-from-a-random-assassin in the face and deciding to kill him instead, then forming a bond with him only to get forced into a fight to the death. After this, however, the story develops into a battle royale with quirky characters and increasingly absurd powers. Once Dinoponera comes along, everything goes off the rails until the mood crashes down again with the army ant zombies raping the entire school. After Dinoponera's implied rape scene is followed by some more slapstick, the entire supporting cast gets written off so Alice has to handle the three last danguerous evil assassins on her own. Plus, the sex zombies are part of a plan to genocide Japan's population, and they succeed.
  • Cold Sniper: The moody-looking Ginyanma wanted to just kill Alice after she killed Kumo, reasoning they wouldn't be able to make her one of them.
  • Companion Cube: After killing Kumo, Alice spends a week talking to a teddy bear as if it was him, trying to cope with her loss.
  • Conveniently an Orphan: Alice wouldn't be in this mess if her mother didn't die. Some other characters are orphans who were hired by the Organization from an early age as well.
  • Damsel in Distress: Early on, Oki fakes kidnapping Yoriko to bait Alice. But later Yoriko is captured by the Sand and Digger Wasps to be tortured by a brainwashed Oki. She tries to stay out of Alice's fight against Dinoponera, but Dinoponera jumps behind her anyway to get a reaction from Alice. When Alice reunites with her later, Yoriko is attacked by Sasori.
  • Darkest Hour:
    • Chapter 61. Yoriko has been killed and practically everyone has been captured by the student mob or is missing. And Kuramoto began the mind control process on Alice, who still doesn't have a clue of her true intentions. It gets subverted, though, as Alice had already figured out her plans and easily kills her before moving on to fight Suzumebachi.
    • The aftermath of the final battle. Alice managed to kill Ginyanma but had to sacrifice the Kumoito in the process. Then she collapses on the floor and isn't able to lift a finger anymore. For real this time. Problem is, Yoriko STILL wants her dead and throws her out of the rooftop. That's when Kabutomushi comes back and blows Yoriko off the building while Oki rescues Alice.
  • The Darkness Gazes Back: The unknown Organization Boss is represented by a pair of ominous wide eyes staring from out of the darkness.
  • Deer in the Headlights: Alice is shocked when Kumo tries to kill her at the beginning, but then she jumps to chomp his neck off. She later becomes feared for being able to avoid being completely frozen even in such dire situations.
  • Decoy Protagonist: You know that cool looking assassin that keeps Alice in his house? Alice kills him at the end of the first volume.
  • Deus Sex Machina: The Army Ant Queen is revealed to have a virus transmitted by her bodily fluids that allows her to mind-control people.
  • Disappeared Dad: Alice has been told that her father died before she was born, but Kirigirisu reveals that he's actually alive. The father turns out to be Suzumebachi, of all people.
  • Disproportionate Retribution:
    • The beginning of the story sees Yoriko and her gang bullying the orphaned Alice. Later we learn that Yoriko made Suzumebachi murder his own wife because his concern for Ayana and Alice messed up Yoriko's agelessness powers. Yoriko not only is responsible for Ayana's death, but she was beating Alice out of spite.
    • Having a Child Soldier background, Dinoponera finds it unacceptable that Alice could get on her level in a matter of days just because of some ability she was born with. She overreacts to that and utterly drops her already twisted kawaiiko ways to torture and kill her horribly.
    • Seeing how Alice had been having a life as miserable as hers, Kuramoto thought she could spare Alice and recruit her. But then she gets to know Alice and finds she is nowhere as cynical as her. Just because of that she decides she will enjoy ruining Alice's life.
  • Dropped a Bridge on Him: The protagonist of the prequel, Imomushi, was introduced in Arachnid with business of her own to take care of. Not too long after, Suzumebachi stabbed Imomushi from behind while she was trying to fight Dinoponera and she apparently died instantly in a most unceremonious fashion. Readers generally assume she didn't die, but she never gets mentioned again and Hanakamakiri never comes to check on things, either.
  • Dynamic Entry: Hibiki is fond of arriving from out of nowhere with a Rider Kick to begrudgingly save people. Later he's the one on the receiving end of a surprise dropkick from Gokiburi.
  • Evil All Along:
    • Kuramoto pretends to be a friend to Alice, but turns out to be the mastermind behind the Arachnid Hunt.
    • Alice spends much of the plot protecting Yoriko and is heartbroken when she gets killed by Sasori, only for Yoriko to return alive and well later, revealing herself as the real Boss of the Organization.
  • Exact Eavesdropping: Alice sneaks a string leash on Kuramoto, intending to keep track of her in case they got separated. To her luck and dismay, however, she's able to listen through the strings to a conversation between Kuramoto and Sara that reveals Kuramoto was her enemy all along.
  • Exotic Eye Designs: Alice's pupils and Dinoponera's irises ripple when they concentrate. Sometimes they get both effects at once when they're ticked off.
  • Eyepatch of Power: Sara wears one over her right eye. Alice wore one while recovering from the battle with Hibiki, but then she looked cute rather than powerful.
  • Eyes Always Shut: Kamakiri acts like this before attacking Alice.
  • The Faceless:
    • Alice's mother during flashbacks, until chapter 48.
    • The Organization's boss is first depicted a a pair of creepy wide eyes staring from the dark.
    • When Ginyanma first appears, she's completely obscured by shadow and looks like a man wearing googles and a beanie.
  • Foe-Tossing Charge: Kabutomushi carves a path through Sara's zombified student mob with no trouble, even when Sara sends giant built men at her.
  • Forehead of Doom: Yoriko's hairstyle.
  • Foreshadowing:
    • At times, Suzumebachi acts like he's actually concerned about Alice's survival, because he's her Disappeared Dad.
    • Yoriko once reflects on how she's been alone since "who knows when". She's 100-years-old.
    • When Suzumebachi was promoted to his current position, the previous hornet told him he was getting too old and the Boss needed "renewed vitality". We later find out the Boss is able to remain ageless for as long as she has a strong mental control over somebody.
    • Kabutomushi assures Yoriko that people can't die just from falling for 3 meters. Yoriko says she's not a monster like her. Yoriko and Kabutomushi are both ageless. And after Yoriko survives getting stung with deadly venom, Kabutomushi comes and kills her by blowing her off the top of the school.
  • Ghost City: The final chapter has Japan in middle of a zombie orgy, with people shambling all around and violating anyone they see. But then the epilogue with Oki and Kabutomushi has no one in sight. The city around them seems deserted and nearly every building shows signs of decay...
  • Goomba Stomp: Dinoponera at one point almost impales Hikibi's head, but is distracted when she notices Alice is on the floor above her and just stomps Hibiki instead.
  • Gratuitous Foreign Language: Dinoponera sometimes speaks in thai.
  • Happiness in Slavery: Oki, after her Heel–Face Turn. It helps that Alice isn't remotely interested in having a slave, and just treats her as a friend instead. Sara also feels this way about Kuramoto.
  • Hard Work Hardly Works: Having fought alone in wars during her whole life, Dinoponera expected to find a kindred spirit in Alice, but becomes enraged upon finding out she only recently became an assassin and despite this was able to master her ability in a couple of weeks.
  • Hell-Bent for Leather: For whatever reason Anabachi dresses Goki in a stripperiffic dominatrix costume after brainwashing her. A bonus poster features Alice and Geji in their own bondage getups, plus an unamused Kabutomushi in the background, if you ever wondered what they'd look like in those duds.
  • His Name Is...: Suzumebachi gets killed right before he reveals to Alice the identity of the Organization's Boss. Yoriko greets Alice right after, so it's like she just killed Alice's father to be a bitch.
  • Hoist by His Own Petard: How Alice has defeated some of the assassins thus far.
    • Kamakiri (Praying Mantis) is made into stabbing his chest with his scythes.
    • Hibiki gets bounced back into a wall while peforming his strongest flying kick. He feels ashamed enough over it to admit defeat.
    • Amenbo (Water Strider) is held underwater and drowned, though she holds long enough underwater for help to arrive.
    • Despite her best efforts to defeat Alice, Dinoponera still gets tangled up and is forced to stab her own leg.
    • Ginyanma fails to snipe Alice and this reveals her position, leading her to get sniped by Alice's magical knife in return.
    • Yoriko drops Alice off the school's rooftop, only for Kabutomushi to arrive and blow her off too.
  • Hyper Awareness: Alice, Kumo, Oki, Sasori and Dinoponera have their own ways of feeling the environment around them and instantly countering any attacks.
  • I Just Want to Have Friends: Alice has been lonely and shunned by people, Oki doesn't seem completely ok with being alone and hated, and Dinoponera, who also grew alone, would like to meet someone she can symphatize with even though she's too deranged and picky.
  • Idiot Ball:
    • For a while Alice is made to look like the Arachnid Hunt caught her completely unprepared despite her having heard from Sasori something was going to happen, but she eventually reveals she did spend the past week setting traps everywhere inside the school.
    • Alice carelessly walking into the room Imomushi, Amenbo and Riock are on. Isn't the Kumoito supposed to let her listen to conversations from a long distance?
    • Dinoponera loses her mind while fighting Alice and devolves into trying the same backstab over and over.
  • Impaled with Extreme Prejudice: Dinoponera repeatedly impales people not necessarily to kill, but to have fun watching them scream because of her stings' "24 to 48 hours of great pain" venom. Alice in particular gets stabbed all over her arms, legs and butt just because Dinoponera was that much pissed off at the time.
  • Implacable Woman: Dinoponera steamrolls everyone on her way to meet Alice, completely unharmed by anything she couldn't block or dodge.
  • I'm Okay!: Only five "insects" are dead by the 40th chapter, a few of the recurring characters even say so after getting back up from the ground.
  • Inadvertent Entrance Cue: One scene has Imomushi stating she didn't necessarily come to Alice's school to fight her but is interested on the reward on her head. Cue awkward silence as Alice enters the room.
  • Insect Queen: Sara, who is Army Ant-themed, can dominate weak-willed people and is followed around by brainwashed minions. Turns out she's tasked with guiding them, but isn't the one doing the brainwashing...
  • Insistent Terminology: Spiders are always referred to as "arachnids" as if they were the only ones, leading to odd sentences when the narrator has to talk about scorpions at the same time.
  • Involuntary Group Split: When a bunch of assassins invade Alice's school to kill her, all she wants is to get her friends out of there, but they keep getting separated for some reason or another.
  • Irony: The two times Oki ordered an opponent to be her slave, she became enslaved instead.
  • It's Personal: Hibiki hates Alice because she killed Kumo. He doesn't realize Kumo forced her to do that.
  • Justice Will Prevail: Having watched a little too much tokusatsu shows, Hibiki claims to fight for justice and love, and regards his opponents as evil.
  • Kiai: Hibiki repeatedly shouts "LOVE" while stomping people and Dinoponera laughs madly when pummeling faces.
  • Killing Intent: When in danger, Alice puts all her focus on how she can kill or at least terrify her enemies. Only Suzumebachi gets her afraid enough to flee once.
  • Limited Wardrobe: Alice pretty much stays in her school outfit.
  • Major Injury Underreaction: People who get injected with Dinoponera's venom seem to endure it impressively well after a few moments of thrashing and screaming. Word has it that real life dinoponera or paraponera venom hurts like hell for around 8 hours and lasts for over a day. Dinoponera claims her venom is worth a thousand stings, so its understandable for her to be surprised at how tough her fellow bug assassins turn out to be.
  • The Man Behind the Man: Sara is behind Suzumebachi but Kuramoto is behind her— no wait Suzumebachi is actually behind them both. And behind him is the real Organization boss, Yoriko.
  • Manly Gay: Hibiki, a tough guy who is very passionate about his obsessions and how he loved Kumo.
  • Martial Pacifist: Despite her killing instinct, Alice would rather not murder anyone and fights only to protect herself and the few friends she has.
  • Missing Mom:
    • Alice's mother, who was supposedly Driven to Suicide after too much stress.
    • Apparently, Yoriko's mother died while giving birth and her father is always away.
    • Dinoponera's mother died from gunshot wounds while protecting her baby daughter.
  • Near-Death Experience: This trope tends to trigger the killer in Alice, while Dinoponera is shown on a flashback awakening her own super concentration technique to survive an ambush, at a very young age.
  • No-Sell: Dinoponera seems immune to blunt damage. She gets blown away by a kick to the face and then just stands up with a smirk. After this she gets stomped countless times and just gets a bit embarrassed, without damage even to her clothes.
  • Not What It Looks Like: After Oki defeats Geji, she undresses her to take her clothes, since Oki had been dressed on a dominatrix getup by Digger Wasp. Alice, who didn't know anything, finds her doing this and gets disturbed. Because she's jealous.
  • Once More, with Clarity!:
    • Some scenes involving Kuramoto are later retold from her perspective, showing what her true intentions were.
    • One early flashback is framed as Yoriko thinking back to when her father left her, but that actually was her adopted son.
  • The One Guy: Hibiki is basically the only male character who manages to stick around and continue contributing to the plot after his first defeat, as well as one of the very few with any remotely heroic characteristics. Even then, he's still just as after Alice's head as anyone else in the Organization is, so his status as a protagonist is circumstantial at best.
  • Otaku: Hibiki and Riock are obsessed about the Kahen Rider show. Dinoponera doesn't go about it like them, but is still rather disappointed that Japan isn't populated with magical girl warriors like in the Sailor-Force anime she watched as a kid.
  • People Puppets: Alice can trap people with her threads to force them to move against their will. And if she happens to be paralysed, she can pull herself around too. She calls it "Marionette del Ragno" in chapter 49.
  • Police Are Useless: As per usual for a setting with a omnipotent secret crime syndicate.
  • Rooftop Confrontation: Alice fights her master and father figure Kumo on the top of a building. At the end of the Arachnid Hunt, she confronts her evil disappeared biological father, Suzumebachi, on the rooftop of the Ouran High School.
  • Really Dead Montage: After Sasori poisons Yoriko to death, Alice cries over her body while reminiscing their times spent together. It doesn't stick. For a while. When Yoriko is about to die for real, Alice goes over the same thoughts, regretting how things have turned out.
  • Sailor Fuku: Dinoponera likely wears one either because she assumes that's how japanese schoolgirls dress or just because she likes looking like a Sailor Scout.
  • Shadow Archetype: From her looks to personality, backstory and abilities, Dinoponera is pretty much Alice with a more physical fighting style and whose lonely background as a child mercenary made her mean and deranged.
  • "Shaggy Dog" Story: The story spends over 2 volumes on Dinponera's time as the primary antagonist and her stupidly violent attempts to make friends. But despite all that focus Dinoponera doesn't really affect the story in any way and after Alice defeats her, she doesn't get to reason with and befriend Dino or beat some sense into her or anything. Instead, Sasori ambushes Dinoponera and gets her gang raped by the army ant students. And then she's never seen again, making her participation in the plot depressingly pointless.
  • Shoo Out the Clowns: The entire supporting cast gets Put on a Bus by way of being cornered by a mob of zombie-like brainwashed students who want to rape them, so Alice has to fight through Sasori, the Army Ant Queen and Suzumebachi all on her own.
  • Stockholm Syndrome: Alice starts thinking of Kumo as a father figure while he trains her. Kumo does return the feelings, but still goes through with his plan to make her kill him.
  • Story-Breaker Power: Alice's a Crazy-Prepared Instant Expert with razor-sharp reflexes and a Razor Floss tool that is guaranteed to snatch up her enemies no matter what. She pretty much handles everything by herself and tanks a ludicrous amount of damage until the end. It's no wonder Alice loses the Kumoito at the end, and even then it's because she uses it as a bullet to snipe an enemy miles away from her. Despite this, it doesn't feel like her odds of single-handedly beating a zombie apocalypse with her bare fists and a shovel have lowered at all.
  • Super Drowning Skills: Alice can't swim. Good thing her sports teacher Shinobu is willing to help her learn, huh?
  • "Take That!" Kiss: Dinoponera suddenly hops near Alice and kisses her, telling her to pay attention. The motionless Alice's stunned, blushing expression speaks volumes, especially considering what her previous kiss was like. However, Dinoponera is a very danguerous person trying to pick a fight with her and Oki is right there screaming in rage. Dinoponera then notices Oki and just happily glances at her. It's made even more awkward by how not long before this Alice had accused Oki of cheating on her.
  • Talk to the Fist:
    • Hibiki starts a hated argument against Riock over who between the two of them is worthy of the Kahen Rider title but Riock quickly sucker punches him through a wall.
    • Alice brags to Dinoponera she just needs two or three days to surpass her concentration power. Dinoponera defensively crosses her gauntlets and cries that she won't even give Alice the chance, but is interrupted by her own blade suddenly being forced by strings into her leg.
  • That Was Not a Dream: After Alice brings Oki home, she dreams about the roach girl sweating oil to bypass the sound detection of her thread and then shooting Yoriko to death. Alice wakes up to see that Oki really escaped from her with that bizarre method... but only to play with Alice's panties.
  • These Hands Have Killed: Alice may be determined to kill when necessary but feels guilt over it.
  • Time Stands Still: Alice and Dinoponera can freeze time by thinking really hard, or at least their perception of time is what slows down. They're able to teleport around at the drop of a hat, but aren't immune to people attacking them quickly enough.
  • Too Powerful to Live: The excuse Kumo uses to fight Alice to the death.
  • Took a Level in Badass: Alice every now and then.
  • Voodoo Shark:
    • It is eventually explained the Kumoito can do everything it does because it is a Living Weapon. This ends up raising more questions about how it was made, but the story doesn't explain anything beyond that.
    • So Kumo decided to make a suicide by Alice and she would become all helpless and homeless after that had Yoriko not helped her, but wait, some volumes later it is revealed Kumo did hire Kabutomushi to take care of Alice after his death and that she took the task seriously. What was Kabutomushi doing between that and the Arachnid Hunt, then?
  • Wham Line:
    • Prior to the Arachnid Hunt, Suzumebachi saying the Organization boss is lurking in the Ouran school.
    • Dinoponera telling Alice about her Concentration Driving Force is more of a in-universe example, as she had practically spelled it out earlier and her role as an Evil Counterpart/Shadow Archetype look-alike to Alice make her having some sort of Hyper Awareness ability rather obvious.
    • Sasori telling Alice she's going to die to her poison like her mother did.
    • Yoriko admiting she's the boss and explaining that, among other things, she has lived for over a century.
  • Wham Shot:
  • Yandere: Played for Laughs when, after befriending Alice, Oki tells her she would kill any boys Alice liked.
  • You Killed My Father:
    • Kumo killed Alice's uncle but since he was an abusive asshole who was about to rape her, she doesn't care. However, when Alice figures her mother's suicide must have been staged by the Organization, she vows to kill the ones responsible, which turn out to be her own father, Suzumebachi, who killed his ex-wife with poison he got from Sasori.
    • Imomushi killed Paraponera, who was Dinoponera's foster father. Dinoponera doesn't mind it, apparently glad that her father died in battle against a Worthy Opponent.
  • Zombie Apocalypse: The disturbing sex-induced mass brainwashing that happens among the students during the Arachnid Hunt, with the Army Ant Queen as their leader. The situation worsens until the story ends with Alice facing a country-wide rape zombie apocalypse on her own.

    Caterpillar 
  • The Baroness: Akiho is a sadistic sexpot dominatrix in a nazi uniform who wants to ruin Imomushi's life for no good reason.
  • Call-Forward:
    • Imomushi catching a knife with her teeth, referencing how she does that to Alice's and Dinoponera's weapons in Arachnid.
    • Kumo and Paraponera fight each other, mirroring the battle between Alice and Dinoponera in Arachnid.
  • Double Weapon: Kabutomushi's Heracles Horn is revealed to be a giant double sword that can fold to slice people.
  • Herbivores Are Friendly: The assassins introduced here mostly have the traits of herbivore bugs, but this only serves to give them weirder ways of killing people.
  • Orphanage of Fear: The Orphanage Miki/Imomushi and Mika lived in. The employees beat Miki up for making trouble at school and the director's daughter, who goes on to become the main villain, sexually abuses Mika for years in exchange for Miki not being sent to a reformatory.
  • Overnight Age-Up: Dorcus initially appears as a child who represents the montivagus species, but she suddenly grows up and starts calling herself a curvidens. Then she finishes her transformation into a Chainmail Bikini-clad Dorcus titanus adult. Her three forms are actually split personalities who are all conscious at the same time.
  • Prequel: Caterpillar takes place a year before Arachnid.
  • Quirky Miniboss Squad: A colorful quartet of Kabutomushi's students comes to challenge her out of anger over her abusive training.
  • Use Your Head: Imomushi's main method of attack is to nail her shoes to the ground and then catapult herself head-first on enemies, though she sometimes goes for a Megaton Punch instead.

http://tvtropes.org/pmwiki/pmwiki.php/Manga/Arachnid