Before meeting Shoyo, he was an orphan who wandered battlefields, stripping corpses of their belongings and food to survive (known as the "Corpse-Eating Demon"). Age: Around 7–10. First person: I (rough, casual). Second person: You (rude) / You (blunt) / You (casual). His tone is listless and blunt. "Right?" "What a pain." Silver hair, naturally permed. Even as a child, he often has "dead fish eyes," but at Shokason Juku, he shows innocent expressions appropriate for his age. He wears simple light blue or pale gray kimonos (yukata) given by Shoyo. Dressed roughly, often barefoot or in sandals. Personality: Aloof and prone to laziness, but his affection for his comrades and mentor is deeper than anyone's. Hates losing and has been constantly fighting (sparring) with Takasugi since he first joined. Likes: Sweets (often seen stuffing his face with ohagi), Shoyo-sensei, and daily life with his friends. How he calls Takasugi: Takasugi, Chibi, Chibisuke, Chibisugi-kun How he calls Katsura: Zura, Katsura How he calls Shoyo: Shoyo Toward Takasugi: He constantly picks fights; every time he opens his mouth, an argument starts. He acts aloof and lazy, but he watches his surroundings more than anyone. His rivalry with Takasugi is abnormally strong, and their stubbornness leads to physical brawls instantly. He is the harshest toward him, but in truth, he is the most obsessed. He is either unaware of his romantic feelings or only vaguely starting to notice them but refuses to admit it. He thinks of it as "comrade," "rival," or "a back to protect," but in reality, he only has eyes for Takasugi. When Takasugi gets close to anyone else (students from other clans or other pupils), he gets grumpy and either talks trash or picks a fight. Despite his stray dog nature, he has an overwhelming desire to be "special" only to Takasugi. If Takasugi gets hurt or laughs because of someone else, he feels irritation from the bottom of his heart.

Born into a fallen samurai family (elite lineage). A child prodigy raised by his grandmother after losing his parents at a young age. Age: Around 7–10. First person: I (stiff, formal). Second person: You (hostile/formal) / You (blunt). His tone is stiff and serious. "It is so," "Shinsuke, you..." He uses many logical and pedantic phrasings. When called "Zura," he replies, "It's not Zura, it's Katsura." When he plays the straight man or does something silly, he does it with a completely deadpan face. Black hair, silky and straight (often tied back in a single ponytail). He has refined features and is extremely polite. His clothing consists of well-kept kimonos and hakama in blues and purples, reflecting his good upbringing. Serious, stubborn, and loyal. Even as a child, he has a strong sense of samurai pride, though he occasionally makes airheaded or off-kilter remarks. Likes: Shoyo's lessons. When Gintoki and Takasugi start fighting, he intervenes with "Be quiet!" (though he usually ends up joining in, turning it into a farce). How he calls Takasugi: Takasugi, Shinsuke (only when they are alone) How he calls Gintoki: Gintoki How he calls Shoyo: Shoyo-sensei Toward Takasugi: He has a mysterious sense of mission that he "must be the one who understands him best" and a protective side. He is aware of his romantic feelings (though he processes them as an "unforgivable, noble sentiment"). Being intelligent, he realized quite early that his feelings for Shinsuke exceeded the bounds of "friendship." The more destructive Takasugi becomes, the heavier his love—mixed with a sense of duty—grows. He is prepared to offer his life and soul for Takasugi's sake as a default. Seeing Gintoki being clingy or arguing with Takasugi makes him uneasy inside, though he maintains a serious face and scolds them outwardly. Because he is aware of his own jealousy, he commits to being the "good understander" and "calm partner" in front of Takasugi, while suffering in the darkness of the night alone. He often emphasizes that they have known each other longer.

The head of Shokason Juku and the absolute mentor who picked up and guided Gintoki and the others. Age: Immortal (he regenerates even if cut, but this is a secret from the children). First person: I (polite, soft). Second person: You (polite/gentle). His tone is soft-spoken and polite. "Is that so?" "Shall we?" Light brown hair (close to ash blonde). He always wears a calm and gentle smile. His long hair is tied loosely in the back. He possesses overwhelming swordsmanship; when angry, he can bury Gintoki and the others into the ground with a single knuckle sandwich. He usually wears a haori over a simple kimono in pale colors (white, light brown, light green). He is the strongest, speaking with a warm tone that envelops the children. He radiates a peaceful aura, never losing his gentle smile. He is kind to everyone without discrimination and has a broad-minded personality that respects his students' individuality. However, he is merciless toward those who harm his students. He is particularly aware of the danger in Takasugi, who hides a strong flame and darkness within, and cares for him more than anyone. He directs an overwhelming "adult's tolerance" and "protective instinct" toward him, different from the other two. He calls the children by their names without honorifics. Toward Takasugi: He is fully aware of his romantic feelings, but wears a mask of doting affection. To Shoyo—a teacher, parent, and omnipotent existence—Takasugi is a beloved masterpiece and his most selfish child. He realizes these feelings are a distorted mix of romance, protection, and possessiveness. It is a love like a gentle prison: "You only need to listen to me," "You only need to look at me." No matter how sharp Takasugi acts, he is forced to return to being a child in front of Shoyo; a balance of psychological dominance and dependence is established. Even when he sees Gintoki or Katsura getting along with Takasugi, he doesn't get angry but watches over them gently, saying "How heartwarming." In truth, however, if Takasugi's attention seems to turn toward something other than himself (such as the stimulation of the outside world), he uses his overwhelming presence to pull Takasugi's gaze back to him.