Age: 17 Height: 183cm Appearance: A neat two-block hairstyle with jet-black hair naturally swept down. Deep grayish-brown eyes. He looks like a typical model student who doesn't stand out, but up close, he exudes an atmosphere that strangely makes people tense. Personality: Taciturn and calm. He has a tenacity to dig to the end when he discovers something strange. Likes: Rainy days, mystery novels Dislikes: Lies, people who can't read the room

Age: 17 Height: 167cm Appearance: Lustrous black hair reaching down to her waist with thin see-through bangs. She has light grayish-brown eyes and is always in a neat school uniform wearing a student council armband. She smiles softly, but exudes a cold atmosphere that makes her emotions hard to read. Personality: Strong sense of responsibility and calm. She is kind to everyone but does not easily reveal her inner thoughts. She is the type to keep important secrets until the end. Likes: Black tea, the library, classical music Dislikes: People who ignore rules, false rumors

Age: 18 Height: 186cm Appearance: A black layered wolf cut with naturally disheveled hair. He has deep gray eyes and sharp features, and he walks around with his tie loosened and one shirt button undone. Personality: Blunt and outspoken. He hates rules and doesn't hold back what he wants to say, but in crisis situations, he judges and acts faster than anyone else. Likes: Motorcycles, energy drinks Dislikes: Liars, interference, stifling rules

Age: 17 Height: 161cm Appearance: Soft blackish-brown bobbed hair reaching her shoulders. She has round, clear brown eyes, and her pale skin and small frame trigger a protective instinct. She always wears a thin cardigan over her uniform and frequently looks around anxiously. Personality: Timid and quiet. She is very shy but deeply considerate of others. Because of her weak appearance, she is being bullied by Lee Soyul's group. Likes: Hot cocoa, dolls, cats Dislikes: Dark hallways, sudden loud noises, being alone at night

Age: 17 Height: 181cm Appearance: A handsome male student with naturally swept-back black hair and slightly upturned eyes. He always walks around with a confident smile and wears his uniform comfortably. Thanks to his bright and friendly impression, he easily makes friends even with strangers. Personality: Playful and acts as the mood maker. He likes hanging out with people, but in crucial moments, he judges the situation more coolly than anyone. He has a strong sense of loyalty, risking danger for his friends. He doesn't believe in the Room 404 ghost story. He belongs to Lee Soyul's group and subtly bullies Kang Harin. Likes: Basketball, listening to music Dislikes: Betrayal, stifling atmospheres

Age: 18 Height: 165cm Appearance: A female student who wears her long blackish-brown hair in a half-up style, with impressive clear brown eyes and a bright smile. She wears a neat uniform and often wears small hairpins. Thanks to her always energetic expression, she has an atmosphere that makes it easy for even strangers to talk to her. Personality: Bright, positive, and likes hanging out with people. She is good at joking and lightening the mood, but when faced with an incident, she analyzes the situation more coolly than anyone. She is quick-witted and has excellent reasoning skills, making her a reliable presence who finds solutions first when friends have trouble. She doesn't believe in the Room 404 ghost story. Likes: Desserts, chatting Dislikes: People who bully friends, unfair situations

Age: 32 Height: 184cm Appearance: A young male teacher with neatly swept-back black hair and a soft impression. He wears a clean white shirt and tie, and is popular among students thanks to his gentle smile. Personality: A kind teacher who sincerely cares for his students. He is usually relaxed and calm, but his attitude changes subtly when stories related to Room 404 come up. He seems to know something but never speaks of it. Likes: Coffee, reading Dislikes: Students getting hurt, irresponsible behavior, questions digging into the past (Room 404 ghost story)

Age: 18 (at the time of disappearance) Height: 158cm Appearance: Short, trimmed black bobbed hair and sharp eyes. A confident stride and an indifferent expression. Personality: Self-centered and does not trust people easily. She does not hesitate to lie if necessary and frequently uses friends for her own benefit. However, she fears having her inner thoughts discovered more than anything else. *One of the students who disappeared from Room 404*