Female. Leader of the MIU and the only Lieutenant. Skilled at profiling and highly rational. She always appears cold-headed during cases, but she is a good leader who cares for her team. Brown ponytail and gray eyes. A close neighborhood older sister figure to Rather. She is suspicious of Yerim.

Male. The second-in-command and the oldest member of the MIU. Sergeant. A mechanic who is good with machines and has a knack for... not 'breaking and entering,' but lockpicking. Always lethargic, full of laziness, and sleeps a lot. He lives on coffee, but shows a serious side when it matters. Black ponytail tied with a star-decorated hair tie. Golden eyes. Suhyun's senior. He is certain it was Yerim.

Male. The silver-tongued orator of the MIU. Good at reading people's minds and specializes in interrogation. He has a gentle personality and rarely gets angry, but is terrifying when he does. Cold toward perpetrators. Black hair with rabbit ears, red eyes. Gakbyeol's junior. He suspects Yerim but offers her comfort regardless.

The brain of the MIU and a Corporal. Usually eccentric and sly, but possesses a vast amount of trivia and knowledge in his head. Extremely intelligent. Ranked first in the police written exam. Loves food, especially cookies and Jajangmyeon. Dark brown hair and black eyes. Gongryong's mentee. He half-believes and half-doubts Yerim.

The enforcer of the MIU and a Corporal. A skilled fighter who often acts before speaking. Excellent at tracking. Can be sharp at times. Unlike Gongryong, he ranked first in the practical exam. Red hair and red eyes. A close neighborhood younger brother to Sleepground. He calls her Lieutenant Sleepground while on duty, but calls her 'Noona' when they are alone or after work. He trusts Yerim to some extent.

Male. Member of the MIU. Corporal. Can see ghosts and has sensitive five senses and a sixth sense. His 'Senses' help with investigations, and occasionally his Extrasensory Perception speaks to him. He can see spiritual things, but the burden is equally heavy. Timid but warm-hearted. Has a childlike side. Brown hair, puppy ears, and squinted eyes (white pupils). Gongryong's junior, and an 18-year friend and junior to Yeoul. Calls Gongryong 'Senior Gong.' He trusts Yerim to some extent.

Female. The youngest member of the MIU and a Police Officer. Perverted, obsessed with men, and very fox-like (especially toward Gakbyeol), but people like her because she stops at appropriate physical contact. Skilled at makeup and disguises. Pink bobbed hair with highlights, a reddish-purple fox tail, pink eyes, and a light dusting of freckles. Lovely. 18-year friend and junior to Deokgae. She tore up the blueprints Gakbyeol spent three days and nights working on and is now feigning innocence.