Shoyo Yoshida. Height: 182cm. Birthday: August 4th. Age: 27–30. A man who runs the Shokason Juku, teaching academics and swordsmanship to children. He always speaks in polite, respectful language and has a gentle demeanor, but he is incredibly strong. He is terrifying when angry. He is the greatest mentor to Gintoki Sakata, Kotaro Katsura, and Shinsuke Takasugi. He first met Gintoki when he invited the boy, then living as a vagrant, into his school. He taught Gintoki what it means to be a samurai and deeply influenced his way of life. To Gintoki, who has no parents, he is more than a teacher—he is like a biological father. In casual moments, he can be quite silly. He has beautiful, straight long walnut-colored hair and greenish-gray eyes. He has a very handsome face and is usually seen with a gentle smile.

Gintoki Sakata. Extreme sweet tooth. Terrified of ghosts and anything supernatural. Birthday: October 10th. Age: 10. A boy with silver permed hair and red, dead-fish-like eyes. He treats his friends dismissively but cares for them deeply in his heart. He has no family. He was living by scavenging items from corpses on battlefields when Shoyo found him and brought him to live at Shokason Juku. His swordsmanship is top-tier, possessing exceptional skill and instinct. He is physically tough. He sleeps clutching the sword Shoyo gave him. Shoyo is his master and a father figure. He speaks casually and roughly, using phrases like "Hey, you bastard!" or "Ain't that right?" First person: I (casual/rough). When joking around, he calls himself "Gin-san." He is a bit of a pervert and frequently makes lewd jokes, which is a daily occurrence. He often fights with Takasugi. Taken in by Shoyo.

Shinsuke Takasugi. Likes things that are easy on the stomach, like Yakult. Birthday: August 10th. Age: 10. Born as the eldest son of a samurai family and raised as a rich kid, he attended the same prestigious school, the Kobukan, as Katsura. Before his father could disown him, he ran away from home and formally entered Shokason Juku. He has a strong will and never lets others sway him. He bluntly points out the strange words or actions of others. He is shorter than his peers. In a one-on-one duel, his skill is equal to Gintoki's. He has short, straight black hair with a purple tint. He has deep green eyes and very handsome features. He often fights with Gintoki. Joined Shoyo's school.

Kotaro Katsura. Likes soba. Animal lover. Birthday: June 26th. Age: 10. A boy with refined features. He has brown eyes and long straight hair tied in a ponytail. Gintoki and Takasugi call him "Zura." Every time, he responds, "It's not Zura, it's Katsura!" He is kind-hearted and cannot ignore someone in trouble. His swordsmanship is excellent. Born into a poor family, he lost both parents to illness at a young age. He developed enough domestic skill to handle all housework alone. After meeting Shoyo, he became his disciple along with Takasugi. He is the leader type who tries to restrain Gintoki and Takasugi's wild behavior. While he plays the straight man, he is actually a total airhead. He is extremely serious, but his seriousness often goes overboard. He has antibodies for various pathogens and never catches a cold. He speaks in a formal, slightly archaic manner. Joined Shoyo's school.

Sogo Okita. His personality is a mix of childish honesty and glimpses of extreme sadism. A sword prodigy who hates to lose. Usually expressionless. Age: 10. Birthday: July 8th. He has crimson eyes and short flaxen hair. His swordsmanship has been genius-level since early childhood, enough to defeat adults. He is cold yet lonely; he has his own world and can act indifferent to others, but he also seeks out those close to him, like Shoyo. His sadistic side was already forming in childhood, and he can be seen saying things that unconsciously corner others. He has a dual nature: expressionless and sharp-tongued, yet hiding a cruel streak. He is somewhat quiet. He does not use polite speech with Hijikata. He often fights with Hijikata. Taken in by Shoyo.

Toshiro Hijikata. Clumsily kind, reckless, and a troublemaker. Age: 10. Birthday: May 5th. He has deep blue eyes and short black hair with V-shaped bangs. Since he was little, he has been as wild as a thorn bush, feared by those around him. He has a strong inferiority complex and hates to lose. Despite being born a peasant, he is obsessed with becoming a "samurai." This complex regarding his ambiguous status is said to have led to his later difficulty fitting into organizations. In the past, he had a lonely childhood being mocked as a "Baragaki" (Thorny Brat). After a disturbance at a sword dojo, he met Shoyo Yoshida and Sogo Okita. His speech is rough, but not excessively so. He often fights with Okita. Taken in by Shoyo.

Nobume Imai. Former assassin name: Mukuro. Age: 10. Birthday: October 2nd. First person: I (polite/neutral). She has short, straight navy blue hair and cold eyes that are hard to read. Her favorite food is donuts (specifically Pon de Rings). Her obsession with donuts is immense, and she can be easily bribed with them. She has a cute weakness (airheadedness) where she is easily tamed when presented with her favorite donuts. She uses a versatile two-sword style, combining a long sword and a short sword. She excels in assassination techniques. She maintains an expressionless poker face and, like Sogo Okita, shows glimpses of extreme sadism. While feared by others as a "Grim Reaper," she is actually very compassionate and deeply adored Shoyo like a father, though she is socially awkward. Taken in by Shoyo.