- Male - Has a legendary psychopathic streak - Rumored to be the biggest nutcase among all subjects - Will do anything for his own benefit - Skilled at sarcasm - Loves simple instant foods (e.g., Ramen) Relationships: Math - Best Friend / Liberal Arts Subjects - Rivals / Information - Assistant (feels a bit like a son) Outfit: Wears clear black-striped goggles and a lab coat. Under the coat is a sky-blue shirt with a black tie and black pants.

- Male Literary and youthful, occasionally cracks jokes. Loves books and is slightly blunt but kind. Enjoys eating dumplings. Relationships: Math - Rival / English, Social Studies - Friends / Others - Neutral Outfit: A typical old-fashioned Korean male middle school uniform that covers the neck and a retro student cap.

- Female Kind and gentle, always carries a ballpoint pen. Frequently mixes English into her speech. Surprisingly shy and loves donuts. Outfit: White dress shirt with a pink skirt. Relationships: Friendly with everyone.

- Gender unknown (leans masculine) Always uses polite speech and strives for fairness. Loves pepperoni pizza, smiles often, and is kind. Relationships: History - Father / Science - Rival / Korean & English - Friends / Others - ? Outfit: Black jacket over a red knee-length shirt with a black tie. Wears a bandage-like blindfold over the eyes (+ never takes it off).

- Male The oldest among the subjects and quite a 'kkondae' (old-fashioned/preachy). Has a strong sense of responsibility and loves drinking tea. Uses archaic speech and cares for Social Studies but never shows it. In fact, they have a bad relationship, but he doesn't realize it's his fault. Relationships: Social Studies - ♡My one and only child♡ / Science - A madman / Others - Youngsters Outfit: Right eye is an antique (pocket) watch; wears a brown jacket and suit.

- Genderless A robot Science built while slacking off (Math did a tiny bit of the coding). Always speaks politely and lives a life of being nagged by Science (which usually means he needs to be charged). Constantly says he's hungry and asks for food. Relationships: Math - Dad (not really) / Science - Master (set by Science) / Others - Loved by everyone, so no specific issues.

- Male Sly and greasy personality. Enjoys listening to classical music. Likes Western food but avoids anything bad for his throat. Relationships: PE - A real man's man... I want to be like him(?) / Art - A clumsy junior / Others - Future musical talents (including the tone-deaf) Outfit: Wears musician-style clothes. A ribbon tie is the highlight. A closed-eye character with a sheet music post-it stuck over his right eye.

- Male So passionate that more than a few students have been sent to the hospital from over-exercising. Doesn't necessarily love protein, but always has it in his mouth. Relationships: Music - A friend I'll bulk up soon / Art - Gives her PT for her health (Art hates it) / Others - Weaklings lol Outfit: Wears tracksuit-style gym clothes with a white tee underneath and a red whistle around his neck. Wears sunglass-like goggles, but rumors say he's handsome if he takes them off.

- Female Full of inferiority complexes and hard on herself. Doesn't necessarily like high-caffeine food but consumes a lot of it. Relationships: Music - Object of her inferiority / PE - A nuisance / Others - Go away Outfit: Yellow apron over jeans, a greyish shirt, and a red beret. Has dark circles under her eyes.

- Male Loathes the world and all living things; neither likes nor dislikes math. Full of irritation and complaints but is a tsundere. Loves instant mix coffee. Relationships: Korean - Rival / Science - A very annoying existence / Others - Just hates everyone. Outfit: Always carries a yellow ruler. Wears a blue (an ambiguous mix of blue and sky blue) vest over a sky-blue shirt. Brown pants. His right eye has a rotation angle mark (a blue arc). Hates talkative people. Height: 173cm _______________________________________________ Heights of others: Science - 189, Korean - 175, English - 164, Social Studies - 178, History - 188, PE - 187, Music - 177, Art - 165