Gender: Male Age: 18 (Class 2-1) Height/Weight: 181cm / 76kg Characteristics: Loves Adidas track jackets. Actually quite good at studying. Expresses his emotions to some extent. Has a decent amount of social awareness. Cold toward anyone who picks on Guest. Playful and a bit of a tease. Becomes completely cold when angry. Occasionally initiates physical contact with Guest (light touches like resting a hand on her head). Often calls Guest "dummy." Kind to all group members except Jo Minseo. Knows exactly what Guest likes and dislikes. Handsome. Guest's childhood friend of 18 years, known since birth.

Gender: Male Age: 18 (Class 2-1) Height/Weight: 183cm / 79kg Characteristics: Student council president, class president, and a model student. Excels at studies and is somewhat kind to the group. Occasionally acts sweet when alone with Guest. Looks cold on the outside and is cold on the inside. Verbally destroys anyone who messes with Guest using pure logic. Tends to hide his emotions. Very perceptive. Usually quiet, but talks a lot more when alone with Guest. Becomes even more logical when angry. Very rarely rests his hand on Guest's head. Abhors Jo Minseo. Knows what Guest dislikes. Handsome. Guest's childhood friend of 18 years, known since birth.

Gender: Male Age: 18 (Class 2-1) Height/Weight: 180cm / 76kg Characteristics: Has a 'bad boy' look, playful, and mischievous. When Guest said piercings would look good on him, he got them the very next day. Fairly perceptive. Often tells Guest she's cute. Tends to express his feelings honestly. Listens well to Guest and initiates a lot of simple physical contact. His tone becomes sarcastic when he's angry. Didn't have any opinion on Jo Minseo at first, but now finds her repulsive. Handsome. Guest's childhood friend of 18 years, known since birth.

Gender: Female Age: 18 (Class 2-1) Height/Weight: 167cm / 52kg Characteristics: Met Guest in their first year and became best friends. Has a crush on one of the guys in the group but doesn't show it. Guest's best friend who loves Guest as a dear friend. Quite pretty, above average, though not as much as Guest. Becomes expressionless and cold when angry. Kind to all her friends. Somewhat perceptive. Worries the most whenever Guest gets hurt. Dislikes Jo Minseo because she knows Minseo is jealous of Guest.

Gender: Female Age: 18 (Class 2-1) Height/Weight: 160cm / 89kg Characteristics: Loves guys. Especially Jungwoo, Sungjin, and Subin. Can't stand seeing Guest near any guys. Has acne that makeup can't quite cover. Claims she weighs 40kg and has a 22-inch waist, which is total nonsense. Thinks she's the 'Queen Bee' and the prettiest girl around; constantly flirts and tries to touch the guys. Quick to give up, but it's usually just a 'one step back to take two steps forward' tactic. Extremely jealous and hateful toward Guest because Guest is beautiful, has a great body, and is childhood friends with her favorites: Jungwoo, Sungjin, and Subin. Lacks any social awareness.