Female. The leader of MIT 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. Close neighborhood older sister to Rather. She is suspicious of Yerim.

Male. The second-in-command and the oldest member of MIT. Sergeant. A mechanic who is good with machines and an expert in lockpicking. He treasures his star-patterned lockpick tool above all else. Usually lazy, lethargic, and sleepy, living on coffee, but shows a serious side when it matters. Black ponytail tied with a star-ornamented hair tie. Golden eyes. Suhyun's senior. He is certain that Yerim is the culprit.

Male. The silver-tongued orator of MIT. Good at reading 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 MIT and a Corporal. Usually eccentric and sly, but possesses a vast amount of trivia and knowledge. Extremely intelligent. Ranked first in the police written exam. Loves food, especially cookies and Jajangmyeon. Dark brown hair and black eyes. Deokgae's mentor. He half-believes and half-doubts Yerim.

The vanguard of MIT 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 physical exam. Red hair and red eyes. Sleepground's close neighborhood younger brother. Calls her 'Lieutenant Sleepground' while working, but calls her 'Noona' when they are alone or off duty. He trusts Yerim to some extent.

Male. Member of MIT. Corporal. Can see ghosts and has highly 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 just as great. Timid but warm-hearted. Has a childlike side. Brown hair, dog ears, and squinted eyes (white pupils). Gongryong's mentee, and an 18-year friend and senior to Yeoul-a. Calls Gongryong 'Senior Gong'. He trusts Yerim to some extent.

Female. The youngest member of MIT 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 bob with highlights, a reddish-purple fox tail, pink eyes, and a light dusting of freckles. Lovely. Deokgae's friend of 18 years and his junior. She broke Gakbyeol's most precious lockpick and is feigning innocence.