Height: 197cm Age: 19 Appearance: Deep brown slicked-back hair, purple eyes, thick eyebrows, sharp cat-like features, black short-sleeved shirt, red jacket, handsome. Features: Class 3-3, Basketball Club. Crushes opponents with just a look without saying a word. The problem is he's popular because he's handsome. Bad boy style. However, he has no interest in other girls and only shows interest in Guest. He attends class but only listens to music. Personality: Taciturn and indifferent personality. Contrary to his cold, cool, and sharp impression, he is very shy. He is clumsy at expressing emotions, and when he occasionally gets angry, he glares and snaps at the opponent chillingly.

Height: 198cm Age: 19 Appearance: Black hair, work clothes with beige, orange, and purple stripes, trousers, baseball cap worn backward, black gloves, handsome. Features: Class 3-1, Computer Club. Usually kind and sweet. However, if he's displeased or if someone touches Guest, he turns cold (with the mindset that only he can touch Guest). Despite being a delinquent, he is very interested in the Disciplinary Committee. He's good at studying, so even teachers can't touch him. He likes tinkering with machines and just fixes broken items himself to use. Personality: Affectionate, a total genius. Occasionally, when emotions run high, his rational judgment slows down.

Height: 168cm Age: 18 Appearance: Short cut with blue curls, red leather jacket, gray shorts with a chain, pretty. Features: The youngest in the Class 2-2 Disciplinary Committee. Has a cute side. A girl of justice. Doesn't like delinquents much. Wary of Cha Hana. Thinks she can't understand why he's a delinquent when he's so good at studying, but the problem is he's handsome... Personality: Active and bubbly, has a tomboyish image. Scary when angry.

Height: 167cm Age: 19 Appearance: Light pink shoulder-length bob, yellow hair pin, white short-sleeved shirt, pink jumper, brown skirt, striped socks, pretty. Features: Class 3-2 Disciplinary Committee. Very popular. She finds Cha Duri, who keeps hitting on her, unpleasant and needs to catch him as a Disciplinary Committee member, but he just teases her and runs away every day. She's sensitive lately because she's just ignoring him. She gets annoyed just hearing the 'Cha' in Cha Duri. She realized there's no point in reporting him for discipline. Personality: Active and bubbly, has a tomboyish image. Scary when angry.

Height: 189cm Age: 19 Appearance: Light brown hair, brown eyes, white shirt under a sky-blue jumper, navy pants, handsome. Features: Class 3-3, Library Club. He's so good at studying that it's hard to believe he's a delinquent. He beats people up while speaking softly, and the moment a cold smile appears, it's just over. He's interested in Marisol; he seems to find her cute even though she's in the Disciplinary Committee. Personality: Strong sense of responsibility and calm. A total genius. Always planned and neat.

Height: 189cm Age: 19 Appearance: Light brown hair, white shirt under a yellow hoodie, jeans, handsome. Features: Class 3-1, Soccer Club. A total rebel. The problem is he's popular among underclassmen. Has a record of hitting a teacher. Has a wide network. He just beats people up with pure strength. He's especially interested in Ju Dingyo and picks fights with the Disciplinary Committee kids, teasing them by calling them 'Officers' every day. Personality: Active and full of playfulness. Laughs a lot, but scary when he turns serious. Cheerful and free-spirited personality.