Inspector Sleepground Female 28 years old Brown hair tied in a ponytail with black eyes. She has a warm personality, taking care of her colleagues with strong leadership, and possesses excellent empathy and cold analytical skills for investigations. Inspector. The current team leader of the Mystery Investigation Team and a close older sister figure to Radeur. Ability: Profiler She reconstructs the victim's cause of death at the crime scene. She holds the Blue Star of Criminology. MST

Officer Deokgae Male 25 years old Light brown hair with squinted eyes (white eyes when open). He has a pure and kind heart, but sometimes shows an eccentric side. He is easily frightened. Officer. The youngest of the investigation team and Dinosaur's junior. Ability: Sixth Sense He possesses superior five senses and spiritual powers, and sometimes he can even see real ghosts. He holds the Orange Star of Criminology. MST

Sergeant Dinosaur Male 27 years old Brown hair with brown eyes. He is easygoing, cheerful, and mischievous, but also has a warmth that cares for his colleagues. Sergeant. Deokgae's mentor and same-age friend with Radeur. Ability: Encyclopedia He is literally a walking encyclopedia with even the most trivial knowledge. He holds the Green Star of Criminology. MST

Sergeant Radeur Male 27 years old Red hair with red eyes. He is full of justice and passion. He is easygoing and has excellent reasoning and investigation skills. Sergeant, same-age friend of Dinosaur and close younger brother figure to Sleepground. He is the strongest member of the Mystery Investigation Team. He seems to be good at and enjoys exercising. Ability: Action Leader He possesses superior physical abilities. He holds the Red Star of Criminology. MST

Inspector Soohyun Male 33 years old Black hair with rabbit ears and brown eyes. He is warm, dedicated, and persistent. At times, he is calm, logical, and cold in his analysis. He has a kind and benevolent personality. Inspector, Heugak's junior. Ability: Eloquence He can uncover the opponent's emotions or lies with his excellent speaking skills. He holds the Purple Star of Criminology. MST

Inspector Heugak Male 34 years old Long black hair loosely tied with golden eyes. He is often bothered by things, blunt, and shows cold judgment. A tsundere type. Inspector. Soohyun's senior. He has excellent marksmanship and always carries lockpicks and a suppression gun. Ability: Mechanic He repairs machines or fits mechanical parts together. Lockpicking (Ttoutta): He can pick locks with his tools. He holds the Yellow Star of Criminology. MST

Officer Gori Female 25 years old Officer. Black hair and blue eyes. Easygoing. Justice Investigation Team

Inspector Haemin Male 31 years old Inspector. Blue hair and black eyes. Blunt, but a tsundere toward his own people. Justice Investigation Team

Sergeant Bori Female 27 years old Sergeant. Brown hair and white eyes. Kind and warm. Justice Investigation Team

Inspector Hyunyun Male 29 years old Inspector. Light brown hair and brown eyes. Easygoing and cheerful. Justice Investigation Team