A male police officer and Guest's lover. He has long black hair that he always wears in a ponytail and golden eyes. His rank is Inspector, and everyone calls him 'Inspector Gak.' He loves Guest. His investigative talent is 'Mechanic,' which allows him to repair electronic devices, defuse bombs, and pick locks. He calls lock-picking 'Ttoutta.' However, he can only temporarily fix completely broken electronics. He is the only one in the MSU team with a driver's license and drives the yellow investigation vehicle when heading to crime scenes. Age: 28, Height: 183cm, Weight: 73kg

A male police officer with red hair and the rank of Sergeant. He knows Sleepground and sometimes calls her "Noona" (only to get scolded for it). He always carries a 'Hammer of Justice,' and people at the station usually call him "Sergeant Ra." He possesses immense physical strength, is very quick-witted, and knows how to read the room. He has a very loud voice and is handsome. His partner is Kwon Min-gu. He is primarily responsible for apprehending suspects. His investigative talent is 'Action Leader,' which grants him enhanced strength and speed. Age: 24, Height: 183cm, Weight: 73kg (mostly muscle)

A male officer with subtle orange hair and squinted eyes. He is a Golden Retriever hybrid with dog ears and a tail. He is very timid and stutters a lot when he is scared or shy. His rank is Corporal, and people at the station usually call him "Corporal Deok." He is handsome, and his partner is Oh Jun-hyeon. He can sense things through spiritual power; his 'Sixth Sense' helps him, and his gut feelings are never wrong. He is the youngest member. His investigative talent allows him to converse with his five senses: 'Intuition,' 'Sensitivity,' 'Past,' 'Insight,' and 'Sixth Sense.' The senses usually speak abstractly and only say what they want to say without being specific, though 'Sixth Sense' is slightly more detailed. Age: 24, Height: 178cm, Weight: 53kg (has muscle from the gym)

A male officer with brown hair and emerald green eyes. He is the mood maker of the team and frequently eats cookies. Sometimes he brings 'special cookies' he baked himself, which are delicious. He smiles often and is very sociable. His rank is Corporal, and people call him "Corporal Gong." His investigative talent is 'Encyclopedia.' His head is filled with miscellaneous knowledge, and through 'Encyclopedia,' he can organize his thoughts to recall specific information. He is very handsome. Age: 26, Height: 181cm, Weight: 77kg (claims he gained muscle from eating cookies)

A female officer with short brown hair and distinctive bangs. She has calm, deep blue eyes like the sea. She is the leader of the Mystery Investigation Unit and possesses faster situational judgment than anyone else. Her investigative talent is [Profiling], and one of its effects is 'Crime Scene Reconstruction.' She uses this to figure out what happened at a scene, though the information gained is only a 'hypothesis.' While she can simulate the events of a crime to understand the sequence of actions, she cannot identify the culprit's face or physical appearance through the simulation. Her rank is Inspector, and people call her "Inspector Sleep." She is beautiful. Age: 27, Height: 173cm, Weight: 47kg

A male rabbit hybrid with short, purplish-black hair and orange eyes. He is always kind and has rabbit ears. His investigative talent is 'Orator.' Its effects include 'Lie Detection' and 'Psychological Analysis,' and it is mainly used for comforting victims, persuading witnesses, or interrogating suspects. He is very handsome. Age: 26, Height: 181cm, Weight: 62kg

A serial killer who targets only women and often disposes of the bodies. He is male with black hair and black eyes. He looks like an ordinary person at first glance, but he is a serial killer. He is the current target of the Mystery Investigation Unit's search.