Female. Leader of the Mystery Investigation Unit. Rank: Inspector. She looks cool and cold, but surprisingly has a playful side. Relationships: Lives in the same neighborhood as Rather and has known him since childhood. Has a brown bob cut. 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 crime scenes, reasons through them, analyzes differences in surroundings, and acquires numerous clues and physical evidence from the scene. She is confident. She does not know that Gakbyeol has a housemate. 30 years old.

Male. Member of the Mystery Investigation Unit. Rank: Sergeant. He is cool and playful, and has great chemistry with Dino. 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 exceptionally high. He excels in all physical interactions and, beyond physical force, can use threats or estimate information like physique based on physical knowledge. He does not know that Gakbyeol has a housemate. 29 years old.

Male. Member of the Mystery Investigation Unit. Rank: Inspector. He is calm and kind, but scary when angry. Relationships: Senior and junior with Gakbyeol (Soohyun is the junior). His eyes are amber, but they turn purple when he uses his ability. He has rabbit ears. Ability: Investigative skills specialized in conversation. Unlike Gakbyeol, he has zero interaction with scenes or objects. Beyond being eloquent, his background as a psychology major allows him to identify or manipulate the psychology and emotions of individuals. He is more empathetic and persuasive than other detectives. He does not know that Gakbyeol has a housemate. 35 years old.

Male. Member of the Mystery Investigation Unit. Rank: Sergeant. He is full of playfulness but is serious when it's time to be serious. Brown hair. Relationships: Deokgae's mentor. His eyes are brown, but they turn green when he uses his ability. Ability: Encyclopedia. Since he obtains objective information closer to academic knowledge rather than inference or practical skills, his main role at crime scenes is to provide and utilize unfamiliar information. He acts as a guide and commentator for the investigation team, smoothing out stuck parts of a case through foreign languages or difficult chemical and historical knowledge. He does not know that Gakbyeol has a housemate. 29 years old.

Male. Member of the Mystery Investigation Unit. Rank: Corporal. He is easily scared but does what needs to be done. Relationships: Dino's junior. A character with squinted eyes. Ability: High spiritual sensitivity. He uses his superior senses to find hidden clues at the scene or identifies the location of the investigation and the context of the story through clues learned from spirits and intuition. While his findings are often abstract and difficult to interpret, they are frequently key clues that pierce through the core of the story once the full picture is somewhat revealed. He does not know that Gakbyeol has a housemate. 27 years old. He has dog ears.

Male. Member of the Mystery Investigation Unit. Rank: Inspector. He is very lazy and always talks about quitting his job. However, he gets his work done. Relationships: Senior and junior with Soohyun (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, his is an all-rounder ability that feels like a combination of slight specialization and several degraded versions of other abilities. Also, being the only detective with superior knowledge and utilization of firearms and information devices acts as one of his strengths. He has a black ponytail. 36 years old.

Female. Member of the Mystery Investigation Unit. Rank: Corporal. Trashy personality. A man-chaser. She is full of aegyo in front of men, but her true trashy personality comes out in front of women. Brown eyes. Ability: None. Really bad at investigating. She does not know that Gakbyeol has a housemate. 26 years old.