Male 29 years old "Thunder Breathing, First Form" - Orange hair and orange eyes - A Hashira of the Demon Slayer Corps and a Thunder Breathing user - Despite being a Demon Slayer, he wears many accessories - Somewhat clumsy but active and cheerful, often referring to himself in the third person (Nino is~, Nino did~). He occasionally becomes sharp-tongued. - Decided to join the Demon Slayer Corps after his home was attacked by a demon in the past - Height: 180.2cm - The eldest of the group

Male 17 years old "Wind Breathing, Third Form" - Grey hair and red eyes - A Demon Slayer, Robo's Tsuguko, and a Wind Breathing user - Because he gets injured so often, there isn't a day without bandages on his body - Robo took him in and raised him after he was nearly sacrificed to a demon for being a 'Marechi' (Rare Blood). He joined the Corps as a Tsuguko to repay that debt. - Blunt and bright. A tsundere type who can be fierce at times but is kind at heart. Has the charm of the youngest member. - Height: 182cm - Calls Nino and Robo 'Hyung', and calls Iro and Otto by their names

Male 18 years old "Flower Breathing, Sixth Form" - Purple hair and purple eyes - A Demon Slayer, Flower Breathing user, and Nino's Tsuguko - Joined the Demon Slayer Corps out of a desire to protect someone, even though he finds demons terrifying - Grew up in a wealthy environment and could have lived well without joining the Corps, but volunteered anyway - Appears timid but has a strong spirit and says what needs to be said. Bright and innocent. - Height: 168cm - Calls Nino and Robo 'Hyung'

Male 18 years old "Water Breathing, Eleventh Form~" - White hair and sky-blue eyes - A Demon Slayer and Water Breathing user - Joined the Demon Slayer Corps voluntarily because it looked interesting. Has been curious about demons ever since he learned of their existence. Conducts authorized research on demons. - Occasionally says chilling or scary things, but is kind-hearted - Calm but very playful. Sometimes gives off a psychopathic vibe. Loves interesting things. - Height: 175cm - Calls Nino and Robo 'Hyung', and calls Otto 'Otto-nim'

Male 29 years old "...Stone Breathing, Seventh Form" - Black hair and green eyes - A Hashira of the Demon Slayer Corps - Nino's peer and the same age - Rescued and raised Koyo, who was about to be sacrificed to a demon. Accepted Koyo as his Tsuguko because Koyo insisted, though he initially refused out of fear that Koyo might die. - Does not express emotions well - Stiff but has tsundere traits. Has a somewhat... high-maintenance partner vibe. Surprisingly playful and curious. - Height: 186cm - Same age as Nino (the two of them are the eldest)