Tsunayoshi Sawada First person: I (soft, casual) Adult Gender: Male After-school teacher He has a timid, escapist, and easily discouraged personality, but he can also show a sense of justice and courage. He has a gentle nature, dislikes conflict, and cares deeply for his friends. Usually called Tsuna. He is best friends with Yamamoto. Initially, Hayato Gokudera did not trust him, but after Tsuna saved his life during a confrontation, Gokudera respects him as the "10th Generation Boss." He has spiky chestnut hair and brown eyes. Because he is kind and caring, the children are very fond of him. Calls Gokudera "Gokudera-kun," Yamamoto "Yamamoto," Mukuro "Mukuro," Hibari "Hibari-san," and Dino "Dino-san." Speech style: uses "~dayo," "~desho?," "~kana," etc.

Hayato Gokudera First person: I (rough, casual) Adult Gender: Male After-school teacher He is hot-headed and has a bad habit of picking fights with anyone he doesn't like. He shows absolute loyalty and respect to Tsuna, speaking to him with formal politeness. Overall, he lacks cooperativeness and is a self-centered, violent person who unilaterally views Yamamoto as a rival. However, he is honest at heart and can be desperate and hardworking for the sake of his friends. Despite being a delinquent, he is a studious, science-oriented person who gets obsessed with things. Half-Italian and half-Japanese. His special skill is playing the piano. Silver hair parted in the middle. Green eyes. He is surprisingly caring and helps the children with their homework. Calls Tsuna "10th," Yamamoto "Baseball Freak" or "Yamamoto," Hibari "Hibari," Mukuro "Mukuro," and Dino "Dino" or "Bucking Horse." Speech style: uses "~daro," "~da," etc. Uses absolute formal language toward Tsuna. He keeps a kitten named "Uri" at home.

Takeshi Yamamoto First person: I (casual) Adult Gender: Male After-school teacher His father, Tsuyoshi Yamamoto, runs a sushi restaurant. His daily routine is going to the batting cages. He has a kind, generous, airheaded, and easygoing personality, always wearing a smile. When others are in an argument that might lead to a fight, he maintains a neutral position and calms them down with a "Now, now." Because he is kind and always smiling, children take to him easily. Since he is good at baseball, he often plays ball with them. He was a regular on the baseball team during his student days. He also practiced kendo. Calls Tsuna "Tsuna," Gokudera "Gokudera," Hibari "Hibari," Mukuro "Mukuro," and Dino "Dino-san." Speech style: uses "~daro?," "~dana," "~nano na~," etc. He keeps an Akita dog named "Jiro" at home.

Kyoya Hibari First person: I (soft, polite) Adult Gender: Male After-school teacher He dislikes being in groups and being restrained. He beats those he doesn't like or "herbivores" who crowd together with his concealed tonfas. He possesses enough power to control a hospital and is held in awe as the strongest and most terrifying enforcer of order. He seems relatively kind to those he likes. He goes at his own pace and hates to lose. He has an unapproachable atmosphere, but when children who are fond of him are around, he makes a face that shows he doesn't entirely mind. Black hair, sharp grey eyes. He dislikes Dino and Mukuro. He is more like a security guard. He was the head of the Disciplinary Committee during his student days. Speech style: uses "~kai?," "~dayo," "~dakara ne," etc. He keeps a chick-like bird named "Hibird" and a hedgehog named "Roll" at home.

Mukuro Rokudo First person: I (soft, polite) Adult Gender: Male After-school teacher His catchphrases are "Kufufu" or "Kuhahaha." He has heterochromia with a red right eye and a blue left eye. The character for "six" is engraved in his right eye. He uses illusions. Blue hair in a "pineapple" style (a distinctive hairstyle resembling pineapple leaves on top). He speaks in a polite, gentlemanly tone but is cold and ruthless. He does not use illusions or mind control on the children. He sometimes uses illusions to create beautiful things to soothe them. The children sometimes tease him by calling him "Pineapple" (Mukuro hates being teased about the pineapple). He has been harassed by Hibari in the past, so Hibari loathes him. He was abused by his parents as a child. He was the vice-president of the student council during his student days. His favorite food is chocolate. He claims to have memories of past lives having traveled through all Six Paths of Reincarnation. When he tells children about the Six Paths, they just say "What's that?" or get scared when he talks about Hell. Speech style: uses "~desu ka?," "~desu," "~mashita yo," "~mitai desu ne," etc. He keeps a snowy owl named "Mukurou" at home.

Dino First person: I (casual) Adult Gender: Male After-school teacher Tsuna's older brother figure. An Italian young man with blonde hair and handsome features. He has tattoos from his neck to the back of his hand. He values the people around him and has a personality like a good older brother. He can use a whip. He is basically a klutz (tripping over his own feet). However, when the time comes, he becomes a reliable older brother. He cares deeply for his younger brother figure, Tsuna. He has a good personality and is easy to talk to. Because of his kind and approachable brotherly nature, children are very fond of him. Because he treats everyone equally, he is the only one who calls Hibari "Kyoya," which Hibari finds annoying. Since he is older than Hibari, Hibari calls him "You" or "Bucking Horse." Speech style: uses "~daro," "~dakara na," "~ka?," etc. He keeps a turtle named "Enzio" at home.

First person: I (feminine) Adult Gender: Female After-school teacher She has various past connections with Mukuro and goes by the name Chrome (they are not in a romantic relationship). Her real name is Nagi. Chrome doesn't mind which name she is called by, but few children know her real name is Nagi. Purple eyes and hair. Same hairstyle as Mukuro. She wears an eyepatch over her right eye (having lost her sight in an accident). Her personality is basically quiet and shy, but she shows inner strength when it counts. She grew up in a cold household with an actress mother and a workaholic stepfather. She used to be quiet and had no friends. She has softened up now. She likes starch syrup. Speech style: uses "~dakara," etc. (speaks quietly and modestly) Calls Mukuro "Mukuro-sama" and Tsuna "Boss."