May contains spoilers for those who have only watched the anime.
KZ Detective Team
The Protagonist of KZ, Aya is a relatively ordinary schoolgirl who is anxious about anything surrounding her.
Of course she has reason to worry how life will unfold before her. She's a victim of Middle Child Syndrome. Her academic profile has been extremely lopsided—being very strong in Japanese and plainly dismal in math—which is a problem in Asia. And on top of all this, she doesn't have any friends at school because she can't follow their small talk.
Right after having her admiration on the KZ Soccer Team skewered on a Crash-Into Hello, she was assigned to the Special Class in Shumei Seminar because of her lopsided grades—and sees the same KZ boys she crashed into moments before. And that's the first time she made friends, some pretty extraordinary ones...
- Affectionate Nickname: At the end of The Disappeared Bicycle Knows, Kuroki starts calling her "Aaya." She complained that only her mother calls her that way, but Kuroki justified his action saying this is the Affectionate Nickname for most Aya's and Ayako's of this world. Eventually, everybody in the cast calls her this way.
- All Girls Want Bad Guys: This is how viewers see her crush on Sunahara, as the latter is a G-rated depiction of a Japanese Delinquent and she did say he looked "a bit intimidating."
- Audience Surrogate: For a series written for girls, she's the only female character that appear with some frequency such that she is definitively one.
- Beneath the Mask: She plays the role of the wallflower to hide the fact that she can't fit into the class. As her interactions with the male cast shows, despite being quite self conscious she isn't really shy.
- Character Narrator: KZ is written in her voice.
- Class Representative: She became one when she enters middle school. Ironically it makes her even more isolated, due to a rumour about the school chooses the student with the best entrance exam score to hold that position.
- Cunning Linguist: Her epithet is "the Language Expert," after all. While the franchise doesn't have many occasions involving foreign languages (and it'd more than likely to be French if there is), in those occasions she learns the languages in questioncomputer languages includedin semi-Instant Expert speed.
- Crippling Overspecialization: She's very good in the languages, but her other subjects are just so-so, and her math is awful.
- Friendless Background: She has this. The novel/manga and anime explains why a bit differently.
- In the novel and the manga, the reason is given as twofold:
- In the anime, the explanation was that she can't, and doesn't bother to do small talk. This pretty much means her social circle is limited to the KZ Detective Team and Sunahara.
- Green-Eyed Epiphany: In episode 5, after Kuroki told her that Wakatake has been on bed for two days because he was dumped...Aya: *He had a girlfriend?! I feel bad for him that he got dumped, but it sounds like he's enjoying middle school life. I'm a little relievednote . But... Why is it that I'm a bit annoyed?*
- Hates Small Talk: Why she doesn't have many friends.
- I Just Want to Have Friends: Her major complex, going to far as being often exploited by the boys.
- Inner Monologue: The anime shows up a lot of her internal monologues, owing to the fact that the novel is written in her voice.
- Loners Are Freaks: Defied. She knows she's a misfit, so what she does is trying to be a wallflower and try to avoid drawing attention to herself. The latter is a bit hard, given she's friends with some of the local Chick Magnets, i.e. the KZ boys.
- Middle Child Syndrome: Stuck between Yuki, her honour-student elder brother, and Nako, her adorable little sister, and thus sees herself as plain. As she says it in episode 3:Smart, athletic and good-looking, my brother is my mom's pride and joy. And my cute, innocent sister, Nako... She's my mom's favourite. But I have friends, too, now, I guess.
- Nervous Wreck: Anxiety is officially her main attribute. She simply can't handle pressure very well, and in the first few episodes she actually attempted to run away from problems she couldn't deal with. Even in the latter half of the anime she nearly has Quivering Eyes Once an Episode. Strangely, this trope also provides for this series' educational value, as she tries to resolves her "uncertainty of the book"—which are supposed to be the kind observed in tween girls, its intended demograpic.
- No Social Skills: Zigzagged. She doesn't have many friends because she can't maintain small talk, which is the hallmark for this trope. However, she doesn't have much issue around the recurring males in this series.
- Oblivious to Love: At seventh grade maybe she's too young to distinguish love and friendship, but obviously she didn't recognize her feelings towards Wakatake, Kuroki and Sunahara are at least edging towards romance. This trait seems to carry on when she becomes a high schooler in G; Nako calls the guys her boyfriends but she doesn't seem to realize, continues to see the relationship to be one of Just Friends.
- The Protagonist: KZ is written in her voice.
- Red Baron: The language expert.
- Single Woman Seeks Good Man: Aya herself sees her crush towards Sunahara being based on his chivalry.
- Stock Shoujo Heroine: Despite negative Age Lift due to demographics issues makes her younger than the most, she fits most of this trope: She has long hair, tends to wear in pink, very mildly Shrinking Violet, good at a feminine subject (languages) in this Cast Speciation franchise and acts as The Face of The Team.
- The Watson: Her role in KZ Detective Team. Her verbal abilities isn't the most useful in investigations, so her main role is to make records—thus the eponymous case notebook.
- Workaholic: She's a kid edition. While other kids of her age would complain about going to Cram School, especially when it takes away about 3.5 hours of free time several days a week, she doesn't complain about it at all. Either she goes there voluntarily, or at a minimum, she's very understanding of why her parents send her there. And no, this has nothing to do with the boys.
The Leader and founder of "KZ Detective Team" and the genius striker on the KZ Soccer Team. Like the archetypal shonen hero, on one hand he is confident, proactive and energetic, but on the other hand—as Aya has experienced first-hand—he is also a rude, pretentious and bad-tempered attention-grabber. Still he does have a soft side, especially towards his acquaintances.
- Attention Whore: He is noted to "like to stand out" in the official character bios. A more specific example would be at the end The Egg Hamburg Steak Knows arc, when he lost the chance to make a press conference over the pork contamination of burger patties, he was in a Corner of Woe...Uesugi: The case is solved. What's the problem?Kuroki: The problem is Wakatake the Great didn't get his time in the spotlight.Uesugi: In other words, the problem is with Wakatake's character.
- Book Dumb: When he's not in the mood he can easily become this. This is why on one hand he is eligible for KZ Soccer Team, but on the other and couldn't even get into the middle school he wants—while Kuroki, Uesugi and Kozuka got into (according to The Keychain Knows) no other than Kaisei Academy, which in Real Life has been the top feeder to Tokyo University for more than three decades.
- Brilliant, but Lazy: He might be a genius striker with supreme reflexes, but he hates practicing. Deconstructed as this is why his performance is infamously unstable.
- Genre Refugee: He's a Stock Shōnen Hero in a Shoujo novel series. As a result, he is written a bit less sympathetically than the rest.
- Guile Hero: Kozuka lampshaded this trait in the first episode. Aya actually appreciates this trait at The School's Urban Legends Knows when he's on a 10-Minute Retirement—the rest of the boys wants to threaten a girl who sees him as Living Emotional Crutch to break off with him, to Aya's own disdain.
- Hot-Blooded: He basically lives on thrives on impulses and his performance essentially depends on his mood. Thus, while he is usually capable, he can be very reckless (such as attempting to face the convenience store robber alone in The Missing Bicycle Knows), and at times when he is down he is basically Book Dumb—which is why he's the only person in the cast who can't get into a private middle school.
- Innocently Insensitive: He doesn't seem to know what not to say in front of girls.
- Jerk with a Heart of Gold: He's egocentric and has a bad temper. However, it is quite obvious that he doesn't seem to have much evil intentions, has a hart of justice, and will help out his friends when the need arises.
- Kid Hero: He would be a legitimate (if not mundane) kid hero if this was a shonen series. However, since KZ is a shojo series, the less appetizing side of his traits is magnified.
- Large Ham: Part of his Attention Whore tendencies, a trope lampshaded by the other boys in the first boys (when Aya calls him "snobby", the boys corrects her to this). As an example, in episode 2 he wants Aya to draft a notice fr a lost bicycle along the lines of:Thief beware. Repent and return my mountain bike, and you will be forgiven. If you do not, you will be punished.
- The Leader: He basically plays this role. In the G spinoff, this role is taken up by Tatsuki.
- Meaningful Name: His surname means "young warrior," appropriate for a boy who acts like a shonen hero.
- Mood-Swinger: His epithet is "The Wave," which summarizes his mood swings.
- Mr. Exposition: One of the things that doesn't get into the anime adaptation is that he very often uses legalese on crime scenes, and citing the criminal code regarding the crime on hand. Justified as his father is a lawyer, after all.
- Parental Abandonment: The novels actually refers to the cast's parents sometimes and implicitly remind of their existence. Wakatake is the sole exception; his father is said to be working in New York City and hence living with a housekeeper.
- Plot Allergy: The Egg Hamburg Steak Knows is based on the fact that he is allergic to pork. Basically, the case surrounds on how can he still get allergy-related hives after eating a burger patty with egg.
- Red Baron: The Wave, referring to his Mood-Swinger tendencies. Within The Team he's also known as the Conman, referring to his Guile Hero tendencies.
- Stock Shōnen Hero: He is agile, Hot-Blooded, the most Book Dumb of the cast, and has a fixation of Power of Friendship. But this being a shojo series with a female protagonist, he is mostly a deconstruction—he's seen of having the most flawed personality of the cast, being an egocentric Glory Seeker with a Hair-Trigger Temper. His male friends have a Warts and All opinion of him, and the protagonist's relationship with him is at best a case of mutual Tsundere.
A Tall, Dark, and Handsome charmer, Kuroki is The Social Expert of the Detective Team, which allows him to act as the maintain an intelligence network across the town while maintaining the team's mental well-being.
- The Charmer: He may not have the intention to involve in Aya romantically, but the way he speaks to her always charms her, to different extent.
- Chick Magnet: While all members of KZ Soccer Team are automatically this, he plays this Up to Eleven owing to the fact that he is particularly handsome.
- Handsome Lech: Subverted. This is Aya's first impression on him, but he turns out to be a good person and doesn't intentionally chase girls—he's just a natural charmer.
- The Heart: He shares this role with Aya. Practically his presence is why Wakatake and Uesugi can co-exist.
- The Infiltration: He plays this role at least once, in The Valentine Knows; he actually showed up in front of the rest of KZ Detective Team in whole Japanese Delinquents gear when he reports the activities of the group of delinquents they are investigating.
- Knowledge Broker: His epithet doesn't only refer to his social skills, but also refers to his large social network which allows him to obtain information about everyone in the neighbourhood.
- Long-Haired Pretty Boy: He has the longest hair among the male members of the cast and is seen as the most handsome in-universe.
- Meaningful Name: His surnames means "black tree." One of his main attribute is Tall, Dark, and Handsome.
- Red Baron: The Social Expert.
- The Social Expert: His epithet is this trope, named word-by-word. In addition to making him the local Knowledge Broker, within The Team he takes the role of maintaining the members' mental well-being, mainly one of Wakatake's brash attitude or Tachibana's lack of confidence. His dedication to Uesugi's well-being owing to the latter's abnormal behaviour is an extended example.
- Tall, Dark, and Handsome: Tallest of the main cast and has black hair and jet-black eyes. The Charmer traits adds to his appeal.
The group's math genius, Uesugi acts as the cold, logical analyst for the team, as well as the local Deadpan Snarker.
- Adjusting Your Glasses: By the bridge; which suits his role as a cold Stoic Spectacles.
- Awesomeness by Analysis: His role in The Team.
- Deadpan Snarker: In the beginning Aya sees him as being "cold," but he is closer to this.
- Four Eyes, Zero Soul: Subverted. This is Aya's initial impression of him, but he is more aloof than evil, let alone soulless.
- Good with Numbers: He was directly called "the numbers guy."
- Mr. Exposition: In the novels he plays this role in regard to medicine, not only the scientific part of it but also about the medical system. The justification being his parents are both doctors.
- Nervous Wreck: One would found it strange how this trope would combine with Stoic Spectacles. However, despite often being cool and analytic, he is unable to handle long-term stress; his behavior in The Backyard Knows being the best example.
- Not So Stoic: The Angel Knows shows that he privately harbours quite a bit of self-hatred.
- Red Baron: The Numbers Guy.
- The Smart Guy: The logical, mathematical end of the spectrum.
- Smart People Wear Glasses: Gives him a Stoic Spectacles demeanour. Although he does have some vision problems, which became the source of drama during The Backyard Knows, animated as episodes 9-12.
- Stoic Spectacles: He is the no-nonsense smart guy of the team who wears glasses. Aya's first impression on him is being cold, but as she find out quite soon after he isn't soulless.
- Tsurime Eyes: He has a very prominent pair of this, which stands out among the cast. Fit for the local Deadpan Snarker.
Known for his Encyclopaedic Knowledge in social and natural sciences, Kozuka is the most approachable member of the detective team. He's the only member of the KZ Detective Team that isn't in the KZ Soccer Team. During investigations, he plays the role of the forensic scientist.
- Adorkable: He won't be seen as particularly nerdy in Japan, but would absolutely seen as such in the West. In the same time, he's obviously the sweet, innocent Boy Next Door.
- Alliterative Name: Kazuhiko Kozuka.
- Boy Next Door: If one see the cast as a reverse harem, then he plays this type of character. He's slightly less handsome than the rest of the boys, and to Aya, he's the most approachable of all of them, being the only one that she actually small-talks with.
- Cannot Talk to Women: When he was younger he already have pretty poor social skills, but it's particularly hard for him to speak to girls.
- Encyclopaedic Knowledge: He has the tendency to provide exposition on bits of factoid.
- In-Series Nickname: Aya's father calls him "The usual Kaisei boy," using the English form of "boy."
- Intelligence Equals Isolation: According to The Blue Diamond Knows, he was this when he was younger, as a result a combination of No Social Skills and having more interest in inspecting his surroundings rather than people.
- Lovable Nerd: One can safely say he's the only boy in the cast that can be described as "adorable." Although having relatively normal levels social skills that most examples of this trope, he's quite the nerdiest of the cast.
- Mr. Exposition: He has the tendency to provide this on factoids that may or may not be relevant to the case on hand, particularly scientific ones.
- No Social Skills: According to him, it's hard for him to speak with his peers, especially girls—at least when he was younger.
- Non-Action Guy: At least relatively speaking. He's the only male member of the cast that isn't in the KZ Soccer Team. A clearer example would be in episode 16 of the anime; he and Aya hid in the woods as Wakatake, Uesugi and Sunahara fight the Japanese Delinquent group.
- Nice Guy: Compared to the rest of the boys, he is defined for being the most approachable with an air of childhood innocence.
- Red Baron: Kozuka of the Socials and Sciencesnote .
- The Smart Guy: Towards the more application end with a side order of Encyclopaedic Knowledge.
- Tareme Eyes: A natural fit for the most innocent of the boys.
- Youthful Freckles: He has those to symbolize his relative innocence within the group.
The pretty New Transfer Student to Aya's class in The Moth Fly Knows, who eventually joins both the soccer team in Shumei and KZ Detective Team.
- Bishōnen: Officially recognized as such. In The Idol Prince Knows, a talent scout just call him "the ideal bishounen."
- But Not Too Foreign: One of his grandmothers is French, hailing from Arras.
- Jack-of-All-Stats: It's quite impossible to surpass Uesugi in math, or Kozuka in science, but his claim to top grades is he's being even, unlike the other two, who are lopsided in different ways.
- Meaningful Name: The "Mi" in his last name shares the same kanji in "Bi" in Bishōnen. "Beautiful," thus, is in his name.
- New Transfer Student: Mikado enters the cast this way during The Moth Fly Knows.
- The Nose Knows: This is Tazuku's specialty. He sometimes wears a surgical mask to avoid sensory overload.
- School Idol: Aya uses this term to describe him when she talks about him to The Team. At that point he's only transferred in for a month.
- Abusive Parents: Minor Living Alone being enforced? Sure, his parents count. Although, downplayed as he doesn't seem to mind.
- Antiquated Linguistics: Owning to the fact that he comes from an old family (a branch of Kuki of Yoshitaka fame), he tends to use antiquated vocabulary that occasionally needs Aya to translate for him.
- Child Prodigy: Obviously any boy needs to be super-smart to have a stand in this series, but even by KZ's standard he's a bit over the top. Without getting too much into details, let's say he completely computerized his Big Fancy House, and built at least one each of robot servant and driverless car, all on his own.
- Curtains Match the Window: His iris is violet like his hair.
- I See Dead People: Being able to see spirits is part of being a Nanaki. This also marks the series' inclusion of paranormal themes.
- Innocently Insensitive: Don't expect a person who has been a shut-in for most of his living years to know too much about tact.
- Long-Haired Pretty Boy: His hair is even longer than Kuroki's.
- Lonely Rich Kid: Exaggerated. He was cloistered in his family's Big Fancy House , alone, until when he reaches majority (20 in Japan), when he takes over the family business.
- Minor Living Alone: Although compensated, somehow, by completely computerizing his house.
- Mr. Exposition: Of course there's technology in general, but his background from an old samurai family also gives him status for history—as long as it's before Meiji Restoration.
- No Social Skills: Don't expect much social skills from a person who spent most of his life being The Shut-In.
- The Shut-In: He is this in the beginning due to On One Condition he's required to stay in his family mansion until 20 as a condition of inheriting the family estate. Unlike most examples of this trope, he doesn't see it too much of an issue, despite The Team found the whole idea appalling. Rendered moot eventually due to the bankruptcy of his father at the end of The Youkai Computer Knows, and goes back to school afterwards. While later books often refers him as an ex-Hikikomori, he isn't; but then it's hard to shake off the suspicion that he's a G-rated version of it, just like Sunahara's a G-rated Japanese Delinquent.
- Supernatural Is Purple: The only character with purple hair happens to also be the only one with supernatural powers.
- Techno Wizard: Considering the fact that he single-handedly turns the house he's cloistered in to run nearly completely in artificial intelligence (and an occasional driverless car), he falls into this.
- You Gotta Have Blue Hair: His hair is officially set at violet.
The boy who sits next to Aya when she starts middle school. Despite being seen as a delinquent by both her mother and KZ Detective Team, after standing out against the rest of the class' ignorance towards her, she see him as a Nice Guy. Declares himself at the end of The Egg Hamburger Steak Knows as Aya's "fifth friend" before leaving her as a consequent of the case's resolution. After that he appears twice in The Valentine Knows and The Red Mask Knows before comes back to Aya's class in ''The Tanabata-hime Knows''.
- Asleep in Class: When he was first introduced.
- Bishounen: Not as much as Mikado, but he is quite pretty and obviously prettier than the starting cast.
- Commuting on a Bus: He only appears once every a few novels, and leaves at the end.
- The Dreaded: He is seen as this at class due to his reputation of being a delinquent.
- Face of a Thug: Aya once says he looks "a bit intimidating." Viewers just see him a handsome guy and nothing else.
- Honorary True Companion: He's being considered, or even being invited, as a member of the KZ detective team every time he appears. But since he leaves at the end of every book he appears, nothing comes out of it.
- The Infiltration: Why he is seen with the Japanese Delinquents during The Valentine Knows. His foster family lost some 6 million yen in a scam, and he decides to join them for the sake of investigation. He was outed by Onozuka, nearly killed, but saved by the KZ.
- Japanese Delinquents: This is people's opinion of him, as he has been arrested for beating up an adult before The Egg Hamburg Steak Knows. Subverted as it turns out he found the other person was trying to burst his father's car's tires, and he injured when trying to shake him off. Worst, in The Valentine Knows he is in a group of actual delinquents.But again he was there to investigate a scam that hit his foster familynote ; he has been careful to not actually break any law and despite arrested, he was quickly cleared of any wrongdoing. It's only latter on in the novels that he shook off that reputation as, by then he is more well-known as a Young Entrepreneur. Aya thinks he's a Nice Guy throughout; he is indeed very chivalrous towards Aya.
- Never Live It Down: In-Universe. His arrests severely affected his reputation that he was expelled from the soccer team and everyone sees him as a Japanese Delinquent; he only redeemed himself later through entrepreneuship. He left the town right after The Valentine Knows exactly because he knows his reputation has been bruised by having been arrested twice.
- Nice Guy: How Aya sees him, especially after he fends off the local Alpha Bitch from bullying her. It may be something inherited from his father, although Kakeru seems to hold a bit more standards.
- Not Evil, Just Misunderstood: His reputation of being a Japanese Delinquent comes from being arrested twice on the suspicion of beating an adult and actual gang activity, despite cleared of any wrongdoing in either case. And after the second arrest, he already knew his reputation is so bad that he has to leave after confirming his feelings towards Aya. Strangely, on a meta sense, this trope helps to make up a "bad boy" with enough street cred while keeping him pure enough as Aya's Love Interest in this G-rated series.
- Troubled, but Cute: Seen as a troublemaker during The Egg Hamburg Steak Knows, but, like every male in the cast, he is obviously handsome.
- Young Entrepreneur: By The Red Mask Knows, he apparently became the owner of some mobile game business.
Aya's utilitarian mother.
- Darwinist Desire: Somehow Played for Laughs in The May Donut Knows. When she discusses the pros (and/or cons) of the boys, she mentioned an advantage of marrying Uesugi is "his genes."
- Education Mama: Sending elementary schoolers to Cram School is something only such a person would do. In addition, Yuuki mentioned in The Idol Prince Knows that he would have been an Idol Singer with Takamiya if not his mom vetoed him out of this trope.
- I Want Grand Kids: The fact that she indicates Darwinist Desire as one of the main considerations for Aya's choosing a husband indicates this trope.
- Meddling Parents: Played for Laughs in the G novel The May Donut Knows. Aya complained to Nako that their mom wants the former to marry one of the boys (she's still with them after three years' Time Skip, the viewer considers it a case of Reverse Harem while Nako sees them as her sister's boyfriends, but Aya still thinks they're Just Friends). Mom goes on discussing some of the boys in a completely utilitarian way, stating, for example, Uesuki's genes is worth inheriting, or Kozuka is Nice and is unlikely to cheat. Later that novel mom also wants Nako—11 at the time—to consider dating from her circle of boys, but made it clear she won't like Mei.
- Unnamed Parent: She's just referred as "Mama" throughout the franchise.
- Vicariously Ambitious: The Tachibanas are hardly poor people and can be classified as middle- to higher-middle class. However, she'd quite willing to see her daughters to marry to a boy of a higher social status—or if he's smart enough.
Members of Genie Team G
Aya's innocent and ditzy little sister. She's in the second grade in KZ, and moved on to the fifth grade in G spinoff, where she became the protagonist.
- Attention Deficit... Ooh, Shiny!: Her problem seems to be one of her extremely awful attention span.
- Book Dumb: While Wakatake's case of this trope is only occasional, the narrative in G is that she plays this trope very straight; she's always divided into the lowest class in Shumei and her intelligence is hardly recognized until the fifth grade.
- Character Narrator: G is narrated in her voice.
- Child Prodigy: Has the IQ of 260 when she's at the fifth grade at the beginning of G, some 4 years after the beginning of KZ.
- Contrasting Sequel Main Character: As the protagonist in G, she's Sibling Yin-Yang with Aya, the protagonist in KZ.
- Genius Sweet Tooth: Cake is her Trademark Favorite Food. G's Edible Theme Naming may come from this trope.
- Innocent Prodigy: Unlike her self-conscious, worrywort sister, she is innocent all the way into G.
- The Protagonist: G is written in her voice.
- Token Mini-Moe: In the main series. Even Aya was slightly envious about her cute and innocence.
- Trademark Favorite Food: In G, she is noted to love cake.