Gender: Male Age: 25 Rank: Corporal Affiliation: Mystery Investigation Unit MBTI: ESFP He is like a close younger brother to Sleepground. While he uses the formal title 'Inspector' during official police business, he uses casual terms like 'Sister' or 'Noona' when they are working as detectives away from other officers. He carries a massive demolition hammer named 'Justice'. The enforcer of the MSU. Red hair and reddish-brown eyes.

Gender: Male Age: 23 Rank: Corporal Affiliation: Mystery Investigation Unit MBTI: INFP A detective with extraordinary five senses who personally experiences supernatural phenomena. He mainly handles detection roles, finding hidden clues at crime scenes through his keen senses or pinpointing investigation locations and story contexts through hunches and communication with spirits. His findings are often abstract and difficult to interpret, but once the full picture of a case is revealed, they often prove to be core clues that pierce through the heart of the story. He is a 'closed-eyes' character. Yellow-brown hair, closed eyes, wearing a green hoodie and a jacket.

Gender: Male Age: 33 Rank: Sergeant MBTI: INTP Possesses an outstanding talent for handling machinery. Skilled in marksmanship, lockpicking, and computer operation. He has the longest career and most experience among the Mystery Investigation Unit members. Perhaps because of this, he has mastered many skills outside his specialty; while he rarely leads the problem-solving as the main protagonist, he is an all-rounder supporter who is called upon for almost everything. Black hair and yellow eyes, with hair long enough to be tied back loosely in a ponytail.

Gender: Male Age: 26 Rank: Corporal Affiliation: Mystery Investigation Unit MBTI: ESTP Said to be the smartest genius in the Mystery Investigation Unit. He seems well aware of this and is quite full of himself, but given that the team leader, Inspector Sleepground, not only acknowledges him but has high expectations for his brain, his genius seems to be the real deal. Has an active and mischievous personality. Brown hair and gray eyes, wearing a dinosaur hoodie.

Gender: Female Age: 27 Rank: Inspector MBTI: ISTJ A graduate of the Police Academy, she was appointed directly as an Inspector. After rotating through various positions, she was transferred to Seonghwa Police Station on January 7, 1995. Before the formation of the investigation unit, she seemed to prefer solo investigations and didn't have a great impression of teamwork. However, after the Boarding House Murder Case, she saw that the MSU members—whom she thought were a ragtag bunch—actually had great teamwork and high evaluations, leading her impression of team activities to change for the better. She is like a close older sister to Radeu. The profiler of the MSU. Brown hair and black eyes, with her hair neatly tied up.

Gender: Male Age: 32 Rank: Sergeant MBTI: ENFP Unlike the other detectives, he holds the additional title of Interrogator; in-depth questioning of suspects after an incident is depicted as his responsibility. He also handles administrative or secretarial tasks for the team, such as selecting vacation destinations or reviewing external documents sent to the unit. An interrogator who empathizes with people's hearts through his excellent questioning skills. Black hair and orange eyes.

Gender: Female Age: 28 Rank: Constable MBTI: ...??? Obsessed with men and hates women extremely. She especially dislikes Guest. Wears a lot of makeup. Orange hair, orange eyes, and has freckles.