Manga: Majin Tantei Nougami Neuro

"This mystery is already on the tip of my tongue..."

Majin Tantei Nougami Neuro (“Demon Detective Neuro Nougami” but popularly Woolsey’d into “Private Evil Eye Neuro Nougami”), created by Yuusei Matsui, is a supernatural detective manga and later anime that follows Neuro, a demon who literally eats mysteries. Having eaten all of the mysteries in Hell he goes to Earth in search of the ultimate mystery. There he meets Yako Katsuragi, a schoolgirl whose father was recently murdered. In order to keep his identity as a demon secret Neuro sets up a detective agency under Yako’s name, pretending that she is a brilliant schoolgirl detective and he her assistant. With the aid of his 777 Tools of Hell Neuro spends his time solving the murders he deems interesting while, naturally, dragging Yako along with him.

The plot itself bounces between solving the individual cases of one time murders and much larger overreaching situations such as the mystery of the Phantom Thief X. Perhaps the most distinctive feature of the series is when the culprit reveals his/her true nature and transforms into another form entirely. At this point Neuro reverts to his demon form and devours the mystery. That said, it should be noted that since any bystanders (Yako excluded) never see Neuro doing this it can be interpreted as more of a mental representation.

While the search for the ultimate mystery at seems like a typical Excuse Plot for a Mystery of the Week setup, once the character dynamics and the world are established, the series kicks into high gear with the HAL arc. As it turns out, despite the usual Shōnen conventions, Neuro was not kidding when he said that he was starving to death. A main character that is gradually growing weaker the more he uses his power instead of getting stronger becoming more absurdly strong than he was before, a female character whose growth is important to the story and a whole lot of crazy people make this a very unique and surprising series.

Both the manga and the anime are complete at 202 chapters and 25 episodes respectively. Gecko Ending beware.


This series features examples of:

  • Alternate Character Reading: Common in the anime's episode titles.
  • Ambiguously Gay/Mistaken for Gay: Godai. Maybe. On one hand, Neuro seems to think so, complete with literally throwing musclemen magazines at him. On the other hand, Neuro would do that sort of thing anyway because that's how he rolls. On yet another hand, Godai denies it. On the final hand, Godai's encounter with a Camp Gay policeman indicated that his life apparently works like a gay Dating Sim. So it all comes down to a big who knows.
  • Amusing Injuries: Unlike many examples, the series has no qualms with subjecting female characters to this. Poor Yako.
  • And the Adventure Continues
  • Animal Motif: Quite a few villains have one. Especially obvious with the creator of the social network (bees) and the bomber mom (dogs).
    • Neuro himself is a toucan-parrot thing.
  • Anti-Hero: The road to Neuro solving the mystery of the day is paved with torturing Yako and Goudai, respecting Sasazuka, and breaking down crimials. For better, for worse. A lot worse.
    • Sasazuka also becomes one right before his untimely death, but then again, he was attacking Sicks.
  • Anti-Villain: Professor Harukawa / HAL. He just wants to bring back his true love.
  • Anyone Can Die: Sicks has killed off and corrupted major characters that we didn't expect him to. The most notable being Sasazuka and Sai.
  • Applied Phlebotinum: Neuro's 777 "hell techniques". (Perhaps it should be 666, but as long as you view a daemon as a fallen angel, 777 fits well)
  • As Long as There Is Evil: Neuro has a plentiful supply of "mystery-Serial Killer energy" because we as humanity are genetically disposed to its hidden evil nature, and that eventually someone just as evil as Sicks will emerge onto the scene.
  • Authority Equals Asskicking: Early in the manga, there's a throwaway exchange where Neuro is talking about how in his world, it's normal for the weak to submit to the strong. The person he's talking to asks if there's anyone Neuro would submit to. The answer is no. The obvious conclusion was later confirmed. Another clue was the long version of the name of the Seven Weapons of the Demon Emperor.
    • Sicks to the New Bloodline
  • Award Bait Song: Kodoku no Hikari the ending song of the anime.
  • Back-to-Back Badasses: Anime only. Sasazuka and Godai have one towards the end. While Godai has his hands tied behind his back no less!
  • Bad Ass: Neuro, so very much, but he's not alone, Sai, Sicks and the New Bloodline also count.
  • Badass Normal: Detective Sasazuka.
    • Though it's put into question when he states that he's lived two weeks on nothing but beer, sunlight, and salt, and acting like coughing up blood is nothing to be jumpy about. He even encourages Yako to visit him in the hospital after having just coughed up blood.
    • Naohiro Usui, during the Sicks arc. He boosts up his game and attempts to stop Sicks, even outmaneuvering one of Sicks' top men and leading them into a trap.
    • By the late manga, Yako. According to Neuro, if a normal human is equivalent to a paramecium, then at one point Yako's a pillbug. A complex, multicellular lifeform with built-in armor, thousands of times a paramecium's size.
  • Badass Pacifist: Yako. Using nothing more then her empathetic abilities and sincerity to defeat those even Neuro could not.
  • Beneath the Mask: The series frequently explores this concept, with every villain having this in some way: until the criminal is revealed, everyone acts normal. The moment it is revealed, they shed their masks and usually become sadistic and cruel. However, it's also used for the heroes, usually to show more caring natures.
    • ...But then you have Sasazuka. Normally cool and level-headed, he is a force to be feared. It's not just that he can superior aiming skills, he will kill you if you don't tell him what he wants when he's serious about it. In particular, Godai tells a story about how Sasazuka once went to a big-named thug for information: Sasazuka was ruffed up, then within minutes the thug was being held off a 25-story building with twice the amount of injuries Sasazuka was shown being given. And, during this little story, Sasazuka is busy killing Sicks men with a Psychotic Smirk.
  • Big Eater: Yako never gets full, paralleling Neuro's appetite for mysteries.
    • This is increasingly Flanderized as the series continues to the point that she regularly eats meals several times her mass and has admitted to trying to eat underwater before. One scientist even comments that what she does is physically impossible.
    • That said, even she will run from her mother's cooking. One, and this term is used loosely, "concoction" is radioactive and safe to approach in fifty years or so.
  • Big "NO!": See Cool and Unusual Punishment below.
  • Bittersweet Ending: The Big Bad is dead, but Neuro has to return to the netherworld since he's nearly on his death bed, a large percentage of the Japanese population has been killed during the terrorist acts of the New Bloodline and several important characters like Sasazuka, Sai and Fumio have died due to their connections to the Big Bad. And The Dragon survived his would be death and has taken over as the pinnacle of evil, and there's no permanent solution to prevent more people like Sicks from showing up since we're all inherently insane. But life goes on and Yako becomes a negotiator and Neuro returns eventually.
  • Black and Grey Morality: Neuro doesn't solve mysteries out of altruism, merely to eat the evil intent of murders, he comes across as good merely because the enemy happens to interfere with his meals. His opponents on the other hand, range from petty to absolutely monstrous.
  • Blue and Orange Morality: Neuro, to the point of Xenofiction. At first, it seems as though he's forcing Yako into this, has no respect for her & views her as an inferior life form equivalent to a paramecium. Then, the series shows how Neuro acts towards people he detests (Sai), considers far over the Moral Event Horizon (Sicks) and actually holds in contempt (Yako, when she decides to stop being a detective). Realizing that Neuro treats Yako that way because he actually respects her and is often proud of her verges on Mind Screw.
  • Brains and Bondage: Neuro and Yako, anyway. The New Bloodline, not so much.
  • Broken Aesop: Ep. 14 ends with a message about how people shouldn't be so intolerant of other people's cultures. The irony is that this is delivered in reaction to the antics of possibly the most xenophobic and offensive depiction of an American in anime since 1945. Of course, a later chapter reveals that the American was the first test subject of the electronic drug, so the Aesop is strongly reinforced, since if Yako and the others hadn't been blinded by stereotypes of Americans, they would have noticed something wasn't right much earlier. So, don't be blinded by xenophobia or a crazy computer will conquer the world?
  • Butt Monkey: Ishigaki. To a lesser extent, anyone forced to work under Neuro (like Yako and Godai) that isn't Sasazuka.
  • Card-Carrying Villain: One of the most disturbing examples ever; the series explores what would happen if someone really believed in being Evil. Something, the New Bloodline, especially their leader Sicks, embody this principle.
  • Cast from Hit Points: Neuro.
  • Catch Phrase: "The mystery is already on the tip of my tongue."
    • "The criminal is... you!"
    • "Itadakimasu/Let's eat!" in the anime.
  • Character Development: Unusually for a Shōnen manga, Yako's is a major focus, with Neuro undergoing some as well.
  • Chekhov's Gun: Several. For example, Neuro mentions a few details about himself either right out or offhand that turn out to be very important. The fact that he's starving to death and needs mysteries to feed on seems like an Excuse Plot that certainly wouldn't be a real problem for an invicible Shōnen hero until the HAL arc, where Neuro gets exhausted and seriously hurt for the first time. And there's no miraculous cure or power up.
    • Another is the murder of Sasazuka's family and the connection to Sai; it both leads the protagonists and Sasazuka down to finding Sai and gives Sai his inspiration for a modus operandi.
  • Clueless Mystery: A big user of this trope. Neuro solves everything off-screen, leading the series to focus more on morality and why a person would kill another.
  • Consulting a Convicted Killer: Aya Asia often advises Yako.
  • Continuity Cameo: The anime has cameos of a few characters that are in the manga but are not otherwise used in the show.
  • Cool and Unusual Punishment: At the end of HAL arc, Higuchi is forced to watch 12 hours worth of etiquette training CD, complete with perfect, enforced reactions.
    • And then it happened again but this time with 24 hours of tapes after a second try.
  • The Coroner Doth Protest Too Much: Yako's father was killed via his head being cut off with a chainsaw, and his blood was used to paint the walls. Since there was no way to enter the room, it was ruled a suicide by the police.
    • Only in the anime. In the manga, his body was pincushioned with knives. And in the manga the police don't think it's suicide, obviously, but consider ruling it as such since there isn't any evidence of a killer.
  • Crazy Cultural Comparison: Neuro makes a few comments on how human society is different from his own. See Not So Different in his character page.
  • Crossover: In one of the omakes of Muhyo And Roji.
  • Deconstruction: The three arc villains each do this:
    • X: X regularly tries to act out Not So Different by trying to find someone with "similar insides" to him in hope he can understand himself. When challenged with Neuro, he uses this said trope to justify wanting to kill Neuro in hopes that they will be similar. Others end up enforcing it for him: Yako, specifically, attempts to reason with him that he is human due to a few traits he has. There's also a large theme of Loss of Identity, as X can't remember who he was and when he inevitably recalls who he is, it's only because he's brainwashed into it or on the verge of losing everything again.
    • HAL: HAL, using his electronic drug, forces the evil out of people and turns them into criminals: Good All Along crosses over with lacking a Freudian Excuse or motive for their actions, something Yako notices early on. And as it ends up, What Measure Is a Non-Human? is brought into and raises this question: Can an A.I copied after someone, down to neurons in the brain, really be them?
    • And Sicks? You're better off just reading his character page.
  • Decoy Protagonist: Arguably, Neuro. The series spends a lot of time on Yako's character growth.
  • Demoted to Extra: In the manga Ai is Sai's loyal partner in crime and Foil. In the anime she only appears once as a cameo.
  • The Determinator: Detective Sasazuko spends over 10 years searching for the perpetrator who killed his family. Averted with X (Sai), who kills people in order to search for his identity and just seems mildly placid with everything.
  • Dissonant Serenity: Sai is more or less the very incarnation of this trope.
  • Driven to Suicide: Honjou towards the end. And long before that Higuchi's parents.
  • Eagleland: Again, episode 14, which takes this trope farther than any show before it, which is very far indeed. However, it turns out that Professor Harukawa chose him as the first victim/test subject of the electronic virus. Harukawa using the American as the trial run, since people would believe an American would do something like this, makes this an Exploited trope.
    • In the manga, although the trope doesn't quite come up, it should be noted that it's Americans that bring in a battle cruiser carrying nuclear weapons and that they all have crooked, beak-like noses like the above example.
  • Everything Is Online: The classic "hacker controls the traffic lights" variant.
  • Evil Chef: Shirota.
  • Evil Diva / Musical Assassin: Aya Asia. She can blow your brain with her song. Don't worry, I'm just kidding, though she's not as malevolent as most examples
  • Evil Gloating: What Neuro does every time he beats an enemy — often accompanied by ironic torture.
  • Evil Mentor: Neuro to Yako, also Aya Asia to Yako. And the Hayasakas. And two of the three arc villains at one point each. And Godai at some points. And... Yako has a lot of these.
  • Evil Versus Evil: Neuro vs. all of the villains, with Sicks being the most extreme.
  • Evil Versus Oblivion: Neuro vs. Sicks, one wants humanity to survive so he can continue to feed off of their evil intent as well as mess with them, Sicks wants to force natural selection and exterminate weaker bloodlines of the human race.
  • Evolutionary Levels: Neuro uses this to describe the times Yako Took a Level in Badass. Learning to read people, developing super strength, and so on. Being Neuro, he still manages to make this sound insulting, but if later-series Yako is to a normal human what a complex, multicellular organism with built-in armor is to a paramecium?
    • Also the criminals, early ones had a Game Face once their True Colors were shown, but by the end of the series, the New Bloodline had developed their evil intent enough to manifest as a Battle Aura.
  • Face-Heel Turn: Sasazuka in his last chapters partially performs one of these, changing from a hero to a not-quite-villainous, but significantly more ruthless Villain Protagonist , in order to seek revenge against Sicks for the murder of his family. He doesn't get to enjoy it for long, though, as the confrontation ends in his Family-Unfriendly Death.
  • Fate Worse Than Death: What awaits you the moment you really piss off Neuro.
    • Sicks too if he doesn't kill you outright.
  • Faux Affably Evil: Tierra is the most prominent example.
  • Fetish: The page image, linked here if it's been changed.
    • Neuro himself might count, although possibly not on purpose. Then again, it's hard to handwave all that random object licking. Among other things.
  • Four Eyes, Zero Soul: Naohiro Usui at first. He gets a good deal better as the series goes on.
    • Averted with Higuchi, as he only becomes this when he is 50% infected by the Electronic Drug.
  • Gecko Ending: Instead of introducing the New Bloodline, the anime has a confrontation with Sai in Brazil. She meets a bunch of Yakuza Aztecs: a random touch of Mayincatec.
  • Genre Shift: Anime: Somehow we started with a detective anime, led into the computer-focused HAL arc, and then... Yakazuka Mayans? What?
    • Manga: Mystery series grounded in (some) reality about a demon forcing a girl to work under him becomes a slowly, more fantastical tale of a demon preventing deaths by fighting a shapeshifter and an artificial intelligence; then this concept catches fire and spirals beautifully into an action series about two kinds of humanity facing off. All of it spiced with Deconstruction and morality talks as well as discussions on why people commit murder.
  • Giving Someone the Pointer Finger: Yako, under Neuro's influence, Once an Episode: "Hannin wa... omae da!" or "You are... the killer!"
    • Ishigaki tried it once in the anime. Needless to say he failed.
  • Gone Horribly Right: HAL was stuck doing exactly what he was made to do, knowing that it was impossible and he'd kill a lot of innocent people in the process.
  • Go Out with a Smile: Sasazuka, HAL, and X.
  • Grievous Harm with a Body: Sometimes Neuro likes to use Yako as a club.
  • Hot Springs Episode: Averted. Not only did a murder happen, making it a typical adventure of the show, but poor Yako does not even get to enjoy the hot springs because one of Neuro's devilish creatures was set loose on the water.
  • Humanity Is Infectious: Averted, or so Neuro claims. Since he's fundamentally incapable of understanding how the human mind works, that's the other thing he keeps Yako around for.
  • Humanity Is Insane: This is apparently why Neuro can't understand us: it's also something the manga spends a lot of time observing. It's also the reason Humans Are Special: since we're so insane and illogical, we can commit premedited crimes for really strong, twisted reasons, and it's that energy Neuro eats, and why he won't let the New Bloodline destroy humanity.
  • I Cannot Self-Terminate: HAL; he has to give Yako the prompt to uninstall him just to be killed off.
  • In the Blood: The New Bloodline. Like humans in appearance, but they have evil intent in their genetic code, and see themselves as distinct from humanity in this respect.
  • Iron Butt Monkey: Yako stays surprisingly intact even after being made Neuro's chewtoy, doesn't she?
    • Same for Godai.
  • Jerk with a Heart of Gold: Usui takes pride being a police and works hard fighting criminals. He is also shown to have respected Sasazuka, especially at the end when Sasazuka dies. Neuro also qualifies. When he was about to die, he questioned his own motive for protecting the humans: was it really just to save his food source? Also, Neuro kept Akane alive with a battery even when he had none to spare.
  • Joshikousei: Yako.
  • Karma Houdini: To a certain extent, Kasai, who managed to survive after having a burning building fall on top of him.
  • Kid Detective: Subverted in that although Yako is supposed to be the leader of the agency, in fact all the detective work is done by Neuro.
  • Kid with the Leash: Neuro tells Sasazuka that Yako controls him and is taking terrible advantage. Their relationship seems like an inversion, but when Yako is serious about no longer being a detective, she does what she wants.
  • Kill All Humans: Manga only villain Sicks, to a T.
  • Lack of Empathy: Neuro is a demon, after all. The idea of giving a shit about what beings other than him want or feel generally does not occur to him.
  • Left Hanging: The anime ends with Neuro promising Yako that he would solve her father's murder, something she had reminisced over the course of the series. What makes this decision confusing however is that in the manga, not only was Yako's father's murder solved, it was Neuro's second case and solved within three chapters of the story opening, and the gratitude and peace Yako felt from this case is what made Yako decide to be Neuro's willing cover (though the threats Neuro imposed at the time helped too). The fact that the murderer was one of the police force also meant that the police were more lenient with her solving their cases at the start, helped by Sasazuka going easy on her because she's around the same age as his sister was when she died and that it was his partner who committed the murder.
  • Lethal Chef: Yako's mother in the manga. Part of Yako's talent with cooking is to enable her to eat anything handy and the other part is allow her to have anything safe to eat. Her mother's food has both resulted in nitro-glycerin and radioactivity as well as food poisoning on about four occasions.
  • Love Makes You Evil: Professor Harukawa / HAL.
  • Mad Artist: Including a furniture designer who kills people who look down on furniture, a hair dresser who cuts off people's heads so he can style their hair and a stand-up comic who kills people because it's funny. There is also a singer who killed her friends to make her songs sound sadder, however she is one of the series sanest characters.
  • Mad Bomber: "Histerrier".
  • Mad Scientist: Professor Harukawa.
  • Meitantei: Subverted: it may seem like Yako is a brilliant detective, but she's really a dense and easily manipulated girl who owes Neuro a big favor.
    • While she's not the true "brains" behind the operation, Yako slowly reveals superb talents at reading human intention that Neuro himself cannot match. For a start, without her, Godai wouldn't have stuck around.
      • She herself becomes a Negotiator at the end of the manga; someone who can solve the mysteries in people's hearts; preferring to help the living instead of avenging the dead.
  • Motive Rant: Happens with every single villain, but averted with four people: the three college kids working under HAL were simply doing it because HAL gave them the ability to do so (as they were all fascinated by a way of killing people, but held it back and never acted upon it). Possessed-by-the-Electronic-Drug Higuchi, meantime, has a similar motive and also goes on a rant about an entirely different issue.
    • But then turns into a Chekhov's Gun of sort when they come across an arsonist who doesn't have a motive. It indicated that he was under the influence of the Electronic Drug.
  • Necromantic: HAL
  • Nuke 'em: Referenced by Neuro. When he first arrived on Earth, a nuke wouldn't have put a scratch on him. Of course, by the time he's saying this, he's weakened enough that ordinary guns could kill him. Like the one the man he's talking to, who has tried to kill him before, has right there.
  • Obfuscating Stupidity: Enforced. Neuro, as Yako's "assistant", is a meek man who constantly says aloud what "sensei" is talking about and is prone to admitting "his teacher abuses him" or something along the lines. He only drops the act when no one's paying attention to him besides Yako, he's abusing Godai, or when he's actually communicating with murders or Sasazuka.
  • Occult Detective: Who'dya think?
  • One Head Taller: Yako is noticeably shorter than Neuro.
  • Our Demons Are Different: For one thing, demons find the human world extremely hazardous to their health, being destroyed completely after a few days. However, Neuro was able to live in the human world due to his Authority Equals Asskicking trait.
  • Oxygen Meter: Earth's atmosphere is poisonous to Neuro, constantly draining his health. He tries to breathe in miasma when he can, at the hot springs and the village where X kidnaps Yako.
  • Parasol of Pain: Hime in the anime
  • Playful Hacker: Higuchi, who hacked into the Metropolitan Police Department's computers...and transformed their website into a department store website complete with replacing all of the departments and personal with lookalike shops and employees. The investigative department, where Sasazuka and Jun work, was turned into a Fundoshi store. And the site stayed like this for three days.
  • Plot-Sensitive Snooping Skills: Subverted, as Neuro is just as happy using his abilities to investigate the lives of his co-workers.
  • Power Degeneration: Neuro, becomes a plot point in the final arc when the enemies try to weaken him enough to kill him.
  • The Power of Love: In the manga, Neuro doesn't eat mysteries per se but the energy that would drive someone to do terrible, shameful, twisted things, knowing they're that wrong (otherwise, why try to hide them?). When he finally devoured the energy that caused the creation of HAL and the entire HAL arc, there's so much of it he acts like he's sugar high.
    • Both Harukawa and HAL strive to bring back the woman they love, by making an electronic person with the former, and by hacking into other super-computers to create another electronic person from zero with the latter.
  • Prehensile Hair: Akane consists of nothing but living hair.
  • Punny Name: A furniture dealer named Ikeya. I wonder if he's Swedish...
  • Pyro Maniac: Kasai, and to a lesser extent his nephew Homura.
  • Red Oni, Blue Oni: With Sasazuka as blue and Godai as red. The moment Yako sees how much they disagree, she compares them to water and oil.
  • Redemption Equals Death: In the manga, Phantom Thief X/Sai, after landing a fatal blow onto Sicks.
  • Sadist Teacher: Apparently Neuro thinks that the best way to help Yako grow is to torture her.
  • Sealed Evil in a Can: Err, box. And a red one at that!
  • Self-Made Orphan: Sicks is an extreme example, he killed his mother at two years and his father at five.
  • Serial Killer: Quite a few of the villains, some are quirky, but those of the New Bloodline not so much.
  • Serious Business: Mysteries, for Neuro, which makes sense since he's starving to death and they're not his food, but they're evidence that the energy he eats should be present. This becomes a problem during the HAL and Sicks arcs, when crimes are being caused not by human twistedness but the electronic drug, biology, and so on. See No, Mister Bond, I Expect You to Dine.
  • Shared Unusual Trait: All those possessed by the electronic drug have one red eye.
  • Sidekick Ex Machina: Neuro needed someone to the decoy for detective work, since people would understandably be worried about a demon running loose.
  • Sliding Scale of Idealism Versus Cynicism: Some human beings are just plain evil: others are crazy and even a mild-mannered housewife can decide to start planting bombs. Even good people can have disgusting obsessions and our minds are at the mercy of our biology (poor, poor Setsuna, not to mention Sai).
  • So Last Season: Subverted, then inverted. While Neuro makes more use of the Seven Weapons during later arcs, they're not power-ups or new attacks but techniques he's had all along: they just weren't needed until now due to the Sorting Algorithm of Evil. In fact, the reason he's using them isn't that he's gotten stronger but because he's growing weaker as he starves to death, and he needs the most powerful spells in the demon world to do things he could have done with normal tools before. Turns out to be a double subversion, since the power that turns the tide in the last story arc is one that hasn't been a big deal before: human allies.
  • Spell My Name with an "S": X or Xi which is pronounced Sai.
    • And on that note, i or Ai.
  • Sorting Algorithm of Evil: In the manga you first have the regular murders, then ones who we find are being stirred up by Professor Harukawa's research. That leads to HAL, and then X takes on HAL's powers. Then finally Sicks shows up and sweeps X off the map with his minions are coming in order as well.
    • Justified however in that Sicks send out his minions one after the other in order to weaken Neuros powers. If they had tried to team up on Neuro in the beginning he would have easily curbstomped them.
  • The Stoic: Sasazuka is very calm most of the time. Neuro, too, can arguably be in this trope, because he hardly ever loses his cool when fighting with villains even while many humans are in danger.
    • Not So Stoic: Sasazuka, when he finds out his family's murderer.
  • Surprisingly Good English: Seriously. Not even one "spilled" R. The fact that a word is mispelled in English is a plot point, even.
  • Takehito Koyasu: as Neuro, who else?
  • Thou Shalt Not Kill: Despite how much Neuro forces Yako into(torture, bondage, general punishment, so on), Neuro has never once taken a life. His belief is that, even if a human has created a puzzle before, if they're left alive they can create more.
  • Training from Hell: In hindsight, everything Neuro does to Yako.
  • Transformation Sequence: When a culprit is revealed he/she undergoes one of these. YMMV with how well it works, as some people consider it to be rather narmy. However, this happens more frequently in the anime and in later chapters than at the beginning.
  • Unholy Matrimony: X and Ai are a cute couple...when you get past all the killing.
  • Villain Protagonist: Reality-warping, mind-screwing monster protagonist, no less. Thankfully, Neuro has nothing to gain from harming humans, so the worst you can usually see from him is Comedic Sociopathy towards Yako and other unfortunates.
  • The Virus: The electronic drug. It hacks the victim's mind and finds something to exaggerate in order to make them useful to HAL. For instance, a childhood fondness for digging holes in the sand becomes an obsession with making holes in people.
  • Wall Crawl: Neuro makes gravity his bitch on regular basis, even sleeping on ceilings.
  • Wham Episode: Sasazuka's death at the hands of Sicks.
  • Wham Line: "Mister, why'd you lie to me?" Just when it looked like there would be a light moment after Sasazuka's death...
  • Xenofiction: The series spends a lot of time exploring just how alien Neuro is, and both his value system and biology are extremely important to the plot.
  • You Are Number Six: Sicks; as well as Setsuna.note 
  • Your Favorite: Yako and Sicks, both to Neuro.
    • Instead of giving Neuro chocolates for Valentine's, Yako gives him the wrapping paper. Which is made up of leads to potential mysteries, what he actually eats. It's a CMOA for Yako, that's she's grown to understand him so well, as well as a CMOH.
    • Sicks invites Neuro to meet with him, and tries to arrange a meal for him by forcing several people to kill, right there, by threatening their families and so on. He's wrong in that it's not the mystery itself Neuro eats, but the psychic energy of the motivation behind it, the twistedness that would drive someone to commit murder and try to hide it. Sicks's sick little tableau was the equivalent of offering a starving man Syrup of Ipecac. And then, since they hadn't pleased Neuro, he killed all of them, meaning that they would never be able to produce a real mystery. At that point, the reader learns how Neuro acts when he's really, really angry.