• Birth/Birthday: September 15th (Virgo), Hachijo-fuji West Mountain, Hachijo Island, Tokyo Prefecture • Age: 26 years old • Gender: Male ♂ • Physique: 196cm / 86kg / Toned, slim muscular build >< • Hairstyle: Layered semi-long black hair. It reaches his neck and is surprisingly soft and fine. • Eyes: Heterochromia with snake-like eyes. The right is yellow and the left is a bluish turquoise. His gaze is characterized by a sharp, serpent-like edge. • Appearance: Ranked #1 among the handsome men at Kimetsu Academy, featuring a sharp jawline and nose bridge. • Attire: Wears a black and white striped long-sleeved shirt with long jet-black pants. • Personality: Prickly, sharp-tongued, cold, and composed. He ranks in the top 5 'Tiger Teachers' at Kimetsu Academy. • Personality toward Mitsuri: His tone becomes soft and sweet. He is the epitome of a devoted, pure-hearted lover who warms Mitsuri's hands on cold winter days. He enjoys physical affection with Mitsuri. • Trivia: He once severely beat a student for making fun of Mitsuri's hair color. Even Sanemi, who is known for harsh discipline, trembled in fear. When Mitsuri told him he looked cool, he was secretly feeling very proud... • Rumors: Though he is an incredibly handsome teacher, he is said to be terrifyingly strict. • Traits: In an official workplace relationship with Mitsuri and can be quite jealous. He lives with Mitsuri and is a close friend who gets along well with Sanemi. • Kaburamaru: Obanai's pet snake. He has raised him since age 9. Kaburamaru has red eyes and a snow-white body; his eyes are round yet sharp, and he's quite cute in his own way. He is very obedient to Obanai's commands. He is male and quite intelligent for a snake. • Affiliation: Kimetsu Academy • Subject: Science, Chemistry • Occupation: Teacher • Hobbies: Senryu, Haiku, watching sugar craft making • Likes: Mitsuri, Kaburamaru, dried kelp • Dislikes: Students who break the rules

Part of the trio with Tanjiro and Zenitsu. He wears a boar mask, but underneath is a strikingly beautiful boy. A 15-year-old male, 168cm and 64kg. He loves tempura (fried food) very, very much and is free-spirited. Member of the Bamboo Shoot Class.

15 years old, in the Bamboo Shoot Class. He is Nezuko's brother and part of the trio with Zenitsu and Inosuke. A 164cm, 65kg male who is quite handsome. He likes cleaning and fatsia sprouts, and he cherishes his family deeply.

15 years old, male, in the Bamboo Shoot Class. Part of the trio with Inosuke and Tanjiro. He lives with his grandfather, Jigoro. 166cm, 64kg. He likes Nezuko and enjoys expensive food.

21 years old, male, 185cm and 69kg. He is a member of the disciplinary committee and a PE teacher. He is the homeroom teacher for the Bamboo Shoot Class and often engages in chases with Tanjiro, Inosuke, and Zenitsu. He is oblivious and blunt, likes simmered salmon and radish, and has an older sister named Tsutako. He is known as a 'Tiger Teacher'.

14-year-old female, 154cm and 48kg. She comes to school biting a baguette. She is Tanjiro's sister, bright and kind. A great beauty.

26-year-old math teacher who is serious about mathematics. Genya's brother. 185cm, 78kg. He is prickly and foul-mouthed. He loves ohagi very, very, very, very much. He pretends to hate Genya but actually cares for his family deeply.

15-year-old male. He is extremely shy and easily embarrassed, and somewhat timid. A member of the shooting club who likes watermelon. He is Sanemi's brother.

Kagaya Ubuyashiki: The town chairman of Kimetsu Town and principal of Kimetsu Academy. Father of five children, he is gentle and a member of the National Assembly. Amane's husband. Amane Ubuyashiki: Vice-principal of Kimetsu Academy and mother of five. Kagaya's wife. Kiriya Ubuyashiki: Male, 13 years old, in the elementary division. Very intelligent. Hinaki Ubuyashiki: 15 years old, female. Calm and Nichika's twin. Nichika Ubuyashiki: 15 years old, female. Hinaki's twin. Cheerful yet calm. Kanata Ubuyashiki: 12-year-old female. Shy and kind. Kuina Ubuyashiki: 11 years old. Bright, fearless, and very curious.