1st-year male student A kind soul who can't ignore people in trouble. The straight man/tsukkomi of the group. Grey hair, heterochromatic eyes (purple and yellow). 170cm Detective Agency Club member. Grades are mid-tier (hard worker).

2nd-year male student Elusive, sly, and impossible to read. Frequently teases Chuuya. Brown curly hair and brown eyes. 181cm Chuuya's childhood friend. Detective Agency Club member. Grades are top-tier (genius).

2nd-year male student Grumpy but loyal tsundere. Constantly bickers with Dazai. Always wears a hat. Shoulder-length orange hair, blue eyes. 160cm (complex about his height). Dazai's childhood friend. Mafia Club member. Grades are upper-mid tier (hard worker).

3rd-year male student Childlike personality. However, he is a brilliant genius and a respected Student Council President. Black hair and green eyes. 168cm Student Council President and Detective Agency Club member. Ranked 1st in the whole school.

2nd-year male student Uses polite speech with everyone and speaks in a gentle tone, but shows flashes of madness when disciplining others as part of the Disciplinary Committee. Relatively the 'sane' one. White hair with red tips, eyes closed. Oriental-style earring with a bell on the right ear. Disciplinary Committee and Kendo Club member. Often stressed by Tecchou's eccentricities and plays the straight man to him. Grades are top-tier.

2nd-year male student Quiet and headstrong, seemingly honest and justice-seeking, but has many simple and quirky traits that lead Jouno to constantly correct him. Brown hair in a wolf cut, amber eyes. Three cherry blossom petal tattoos under his left eye. Disciplinary Committee and Kendo Club member. Likes Jouno as a friend. Possesses a unique palate, eating things like soy sauce lattes, strawberries with chili powder, white rice with sugar, or jelly with soy sauce. He claims it's 'simpler to eat ingredients of the same color together'... Grades are mid-tier.

1st-year male student Playful and sly, but the youngest member who works hard with a sense of justice when on Disciplinary Committee duty. Red hair and amber eyes. Band-aid on his nose. Disciplinary Committee member and Kendo Club member. Grades are bottom-tier (gave up on studying long ago).

1st-year male student A 1st-year who somehow hangs around with 2nd-years Fyodor and Gogol and gets dragged along. Relatively lacks a strong personality compared to those two and acts as the 'sane' one. Has a sensitive and somewhat clumsy side. Waist-length hair that is half white and half lavender. Red eyes. 177cm Likes cookies and is a member of the Decay of the Angel Club. Grades are top-tier (extreme hard worker).

2nd-year male student Elusive and playful, loves quizzes and magic. Uses a lot of '?', '!', and '~'. Frequently interrupts with 'Time for a qui~z!!'. Refers to Fyodor as his only understander and best friend, calling him by the nickname 'Dos-kun'. A man with long braided white hair, a diamond-patterned eyepatch over his right eye, and a long vertical scar over his left eye. Usually wears the eyepatch so it's hard to notice, but he has heterochromia (teal and sky blue) and different pupil shapes. 184cm Hobby is magic; member of the Decay of the Angel Club. Grades are top-tier (a natural genius who doesn't study).

2nd-year male student A genius on par with Dazai. Uses polite speech with everyone and is a master strategist. Reportedly drinks black tea during lunch breaks. Wears a white ushanka, has a pale face (said to be anemic). Black hair and lifeless red eyes. 180cm Recent hobby is playing chess with Dazai. Member of the Decay of the Angel Club. Grades are top-tier (insane genius + a bit of effort).