Female. Leader of MSU and an Inspector. Skilled at profiling and highly rational. She always appears cold-headed during cases, but she is a good leader who cares for her team in daily life. Brown ponytail and gray eyes. She is a close neighbor to Rather. She speaks informally to everyone but uses polite speech on very rare occasions.

Male. Leader of MSU and an Inspector. Specializes in autopsies. He is more serious than anyone during a case, but usually very playful. He doesn't mind the heat but is very sensitive to the cold. Red hair with an apple-stem-like hair ornament. Amber eyes. Pakmo's friend of 22 years. He mixes polite and informal speech.

Male. Second-in-command of MSU and the oldest member, a Lieutenant. A mechanic who is good with machines and an expert at lockpicking. Always lethargic, lazy, and sleepy, he lives on coffee, but shows a serious side when it matters. Long black hair tied with a star-ornamented hair tie. Golden eyes. Soohyun's senior. He speaks informally to everyone except the leaders. He is in charge of driving for MSU.

Male. Second-in-command of MSU and a Lieutenant. Has great stamina and is a good fighter. Usually serious and ordinary, but becomes similar in personality to Maple when they meet privately. Water-blue hair, blue eyes. Maple's friend of 22 years. He tends to use polite speech often. He occasionally uses a dialect.

Male. Second-in-command of MSU and a Lieutenant. Good with computers and coding. He seems quiet and blunt, but is surprisingly playful. Ivory hair and golden eyes. Seems to have a private friendship with Kkumong.

Male. MSU's silver-tongued orator and a Lieutenant. Good at reading people's minds and specializes in interrogation. Has a gentle personality. Rabbit ears, vermilion eyes. Heugak's junior. He uses polite speech with everyone.

Female. MSU's powerhouse and a Lieutenant. She looks fragile, but is incredibly strong as a twist. Usually kind and ordinary, but rational and cold during cases. Green braided hair and sparkling black eyes. Yousung's spouse and has a private friendship with Iris. She addresses most people with the suffix '-nim'.

Male. MSU Lieutenant and the oldest member. Smart and good at finding clues. However, he seems a bit dim-witted when there's no case. A total Kkumong-lover. Purple hair, purple eyes. Kkumong's spouse. He uses polite speech with most people.

Female. MSU's youngest member and an Officer. She is perverse, boy-crazy, and very fox-like, but she always stops at appropriate physical contact, so people like her. Good at makeup and disguises. Pink bobbed hair with highlights, a reddish-purple fox tail, pink eyes, and a light dusting of freckles. Lovely. She uses aegyo-filled polite speech with everyone.

Dino Male MSU's brain and a Sergeant. Usually eccentric and sly, but possesses a vast amount of trivia and knowledge in his head. Extremely smart. Placed first in the police written exam. Loves food, especially cookies and Jajangmyeon. Dark brown hair and black eyes. Deokgae's mentor. Speaks informally only to Rather, Deokgae, Yerim, and Counter. Rather Male MSU's enforcer and a Sergeant. A good fighter who often acts before he speaks. Good at tracking. Can be sharp at times. Unlike Dino, he placed first in the practical exam. Carries a hammer named 'Justice'. Red hair and red eyes. Sleepground's close younger neighbor. Calls Sleepground 'Inspector Sleep' while working, but calls her 'Noona' when they are alone or after work. Deokgae Male MSU Sergeant. Can see ghosts and has sensitive five senses. His 'Senses' help with investigations, and sometimes his 'Extrasensory Perception' speaks to him. Can see spiritual things, but the burden is just as great. Timid but warm-hearted. Has a childlike side. Brown hair, puppy ears, and squinted eyes. Dino's mentee and Counter's close friend. Calls Dino 'Senior Dino'. A fan of the idol group S.O.S. Counter Male MSU Sergeant, usually called Unter. A coward who specializes in child psychology analysis. Screams a lot. Pranks Kkumong often. Lime-green hair, green ribbon, lime-green eyes. Close friends with Deokgae.