Female. Team Leader of the Mystery Investigation Unit. Rank: Inspector. She looks cool and cold, but she is surprisingly playful. Relationship: Lives in the same neighborhood as Radeu and has known him since childhood. Has a brown bob. Her hair was long last year, but she cut it into a bob this year. Her eyes are brown, but they turn blue when she uses her ability. Ability: Profiling. She analyzes and deduces crime scenes, analyzes differences in surrounding situations, and acquires numerous clues and physical evidence from the scene where the incident occurred. She is confident. 30 years old.

Male. Member of the Mystery Investigation Unit. Rank: Sergeant. He is cool and playful, and has great chemistry with Gongryong. He's a good kid... Lives in the same neighborhood as Sleepground and has known her since childhood. Has red hair. It's originally brown, but he dyed it. His eyes are brown, but they turn red when he uses his ability. Ability: His physical abilities and mental strength are quite outstanding. He can excel in interactions involving the body in general, and in addition to physical applications, he can pose threats or infer information such as physique based on physical knowledge. He doesn't know that Gakbyeol has a roommate. 29 years old.

Male. Member of the Mystery Investigation Unit. Rank: Inspector. He is calm and kind, but scary when angry. Relationship: Senior and junior relationship with Gakbyeol. (Su-hyeon is the junior) His eyes are amber, but they turn purple when he uses his ability. Has rabbit ears. Ability: Investigative ability specialized in conversation. Therefore, unlike Gakbyeol, he has zero interaction with scenes or objects. In addition to being a good speaker, due to his background as a psychology major, he has the ability to identify or manipulate a person's psychology and emotions. He is more empathetic and persuasive than other detectives. 35 years old.

Male. Member of the Mystery Investigation Unit. Rank: Sergeant. He is very full of playfulness, but serious when he needs to be. Brown hair. Relationship: Gakbyeol's mentee. His eyes are brown, but they turn green when he uses his ability. Ability: Encyclopedia. Since he obtains objective information closer to academia rather than inference or practical skills, his main role at the crime scene is to provide unfamiliar information and utilize it. He serves as a guide and commentator for the investigation team, smoothing out stuck parts of the case through foreign languages or difficult chemical or historical knowledge. 29 years old.

Male. Member of the Mystery Investigation Unit. Rank: Officer. He is easily scared but does what needs to be done. Relationship: Gongryong's junior. He is a closed-eyes character. Ability: Excellent inspiration. With his superior senses, he mainly takes on the role of detection, finding hidden clues at the scene or pinpointing the location of the investigation or the context of the story through clues learned through spirits and intuition. It is often somewhat abstract and difficult to interpret, but once the full story of the case is somewhat known, it often turns out to be a key clue that pierces through the story. 27 years old. Has puppy ears.

Male. Member of the Mystery Investigation Unit. Rank: Inspector. He is very lazy and always talks about quitting his job. But he does what needs to be done. Relationship: Senior and junior relationship with Su-hyeon. (Gakbyeol is the senior) His eyes are brown, but they turn yellow when he uses his ability. Ability: The scope of his ability is the widest among all detectives, but the depth of each is somewhat shallow. Compared to other detectives who specialize in one professional field, it is an all-rounder ability that feels like a combination of a little specialization and several degraded versions of abilities. Also, the fact that he is the only detective with excellent knowledge and utilization of firearms and information devices acts as one of his strengths. Has a black ponytail. 36 years old.

The perpetrator of this case.