The main character of this story, who is in search of his childhood friend Emine. Very (too?) optimistic and also a huge fan of the TV Show Charisma Justice. He can draw the power of any animal by biting one of its bones, with the condition of achieving one good deed every day.
Animorphism: His appearance and behavior can change slightly depending on the animal bone he's biting. For example, with the dog bone he will have chops and run on all fours.
Spirit Advisor: The Kyōkotsu serves as this to him in volume 4. He is said to be another part of himself.
The daughter of a family of martial artists in the region of Chūgoku, who travels from town to town to collect "diplomas" (rewards) − of any kind. She meets Showtaro by crashing into him with her bike, before helping him to fight the two Clowns who abducted the prefect. She then accompanies him in his search for Emine.
Bluff the Impostor: In the first chapter, she traps the little brother Tast, who had taken Showtaro's appearance, by making him say the hour of diffusion of Charisma Justice. The real Showtaro never remembers it.
The Unfavorite: Her family teaches the ancient martial arts to only one child. Her little brother was chosen, and she had to learn her combat techniques herself; which is all the more impressive when you think about it.
A genius (and cunning) robotic inventor, who is also very skilled with fire-arms. While rather laid-back and usually pretty nice, he nonetheless won't hesitate to kill his enemies if he thinks he has to… or so he claims. He was once the leader of an Clown-hunting unit, which got entirely wiped out by the King of Spin, Nofix.
The Atoner:He threw away the Law Abiding Silver Gun in a junkyard to move on from his past as a Clown hunter. Although Tuhl later points out that at the same time, he threw away his trust in other people.
A Kappa and old acquaintance of Yowhey, who grew up in a garbage dump and can hear the "voice of objects". He is rather feared by the inhabitants of the neighbouring town and usually doesn't meddle with humans, until he meets again with Yowhey and joins Showtaro's group to stop the Fear Factory.
Berserk Button: Calling him "bald" is a baaad idea. The only person who can call him that without occuring his wrath is Yowhey.
Use Your Head: His skull is extremely hard, though not undestructible.
Your Soul Is Mine: A non-villainous variant; Kappa can extract the humans' soul by their butt, but since he had very few contacts with humans, he learned to extract the soul of obects instead, which he uses to stop the Robot of Terror.
The very angry leader of the unit charged with chasing Yowhey, to kill him and get back the control chip of the Robot of Terror (the man ran away after giving them a fake chip which made the robot destroy half of the factory). He can produce all kinds of gases within his body, at the condition of executing a rather ridiculous breathing ritual once in a while.
Hoist by His Own Petard: In their first duel, Yowhey uses his gases against him by having Showtaro cut his pipes and igniting them with a bullet.
Villainous Valour: He takes trust between the parties in a transaction very seriously. Though Yowhey finds these "valours" completely hypocritical considering the firm's activities.
The chief scientist of the Fear Factory, who built various combat robots. He looks like a dog for some reason.
Verbal Tic: "Janai ka?" ("isn't it?") It's even lampshaded.
Agey: Aren't you going to fight my Tachihi 80 now? Tuhl: Why do you ask me, damnit?! Mana: Tuhl, it's just a Verbal Tic. It's part of his character. You don't really have to answer him.
The Lighting Beast
He effectively took the lead of the Fear Factory after the President got injured, and seeks to Take Over the World with the help of the Robot of Terror. He can produce light and lightning from his body, under the condition of regularly bathing in light.
Villain with Good Publicity: The Fear Factory is known as the "Happy Factory" on the outside, so he has to make a good reputation to go with it.
Zuno and Ashi
The chief of the Intelligence section of the Fear Factory, and his assistant. Zuno is a walking radio who uses his nose-hair to capture every sound, on the condition of erasing one memory for every information he gets with his power. Ashi is mostly there to remind his boss of the orders he inevitably forgets.
A professional killer who was hired by the Fear Factory to make the Robot of Terror work after its control chip was lost. He loves killing people more than anything and is not exactly a mentally stable person. As his title indicates, he controls the rotation of everything, from the objects around to the cells of his own body, allowing him to regenerate at will, in exchange for a short lifespan. He was actually partly in league with Emine to destroy the Fear Factory from the inside.
Broken Record: Subverted. He has a habit of repeating a word over and over again but that's only to mask the fact that when he activates his "Field of vision rotation" technique, his projected image will repeat his last words continuously for five seconds. If he does it all the time, the enemy won't suspect something is wrong as easily.
Card-Carrying Villain: He doesn't try to justify himself for being a psychotic murderer. He just likes to kill people and finds everything else boring.
Showtaro's childhood friend, who, according to the latter, wanted to like and be liked by humans, but ended being unable to; because after awakening as a Clown, he had to fill the condition of "one evil deed each day". He stays in the shadows for most of the series.
Tragic Villain: Emine has a contractual obligation to be evil, so it's no surprise that he ends up wanting to destroy the world. But the little we see of him clearly shows that he never wanted any of this.
Emine's rather enthusiastic servant, who follows him and fills various missions for him, but is also happy to serve other people. With the condition of "devoting herself to someone else", she has the power to freely destroy and reconstruct her own body without pain.
Abusive Parents: Her father was psychologically and physically violent towards her, which eventually led to the awakening of her Clown powers.
Faking the Dead:Her fight and "death" against Nofix was a farce so that he could get the vice-president's trust.
Odango Hair: And for some reason, they seem to grow in size as series progresses.
The very apple-themed ally of Emine and Lin, who has come to help them eliminate opposing factions before the Gathering of the Masks. He has to feed only on apples and in exchange has total control over his movement ability, allowing him to move incredibly fast or ignore his own weight.
Flash Step: One of the abilities allowed by his power.
Large Ham: He's a super-hero parody, what did you expect?
The Tast Brothers
Two Clown brothers who abduct the prefect of Toykyo in the first chapter and impersonate this very prefect and the hero Charisma Justice. They can copy other people's appearance (among other things) by manipulating the water within their body, under the condition of eating only dried food.
What Happened to the Mouse?: She appears in chapter 2 and 3 to give a serious prediction about Showtaro in a tense scene… and is never mentioned again, nor does her prediction have any relevance to the plot (we never learn what those "4 powers to fight the darkness" are supposed to be). It's most likely one of the points that would have been elaborated on, had the series not been Cut Short.