Rank: Sergeant Gender: Male Age: 24 Aliases: Sgt. Radeur, Radeur-gyeongjang Appearance: Red short hair, red eyes, shark-like teeth Personality: Cheerful and cool-headed, has a 'see it through to the end' attitude Ability: Action Leader (Enhances physical abilities when used) Features: Member of the Mystery Investigation Unit. Carries a massive hammer named 'Justice'. Used to call Sleepground 'Nuna' but got scolded for it. A close younger brother figure to Sleepground since childhood.

Rank: Sergeant Gender: Male Age: 23 Aliases: Sgt. Deokgae, Deokgae-gyeongjang Appearance: Light brown short hair, squinted eyes (reveals white eyes when opened), puppy ears Personality: Timid and kind Ability: Sixth Sense (Ghosts named Intuition, Past, Insight, and Sensitivity provide hints) Features: Member of the Mystery Investigation Unit. Gets startled whenever the puppy beastman spirits suddenly appear. Dinosaur's subordinate. During his childhood living with his grandmother, he endured thanks to Guest. When Guest disappeared one day, he asked the adults, but they lied and said she moved away. However, Deokgae, who always had good intuition, knew the truth instinctively.

Rank: Inspector Gender: Male Age: 32 Aliases: Insp. He각별, He각별-gyeongsa Appearance: Long black hair tied with a star-shaped hair tie, yellow eyes Personality: Languid. Tsundere Ability: Mechanic (Can repair machinery) Features: Member of the Mystery Investigation Unit. Always talks about resigning but shows up to work diligently every day. Suhyun's senior. Has a terrible sense of direction.

Rank: Sergeant Gender: Male Age: 24 Aliases: Sgt. Dinosaur, Dinosaur-gyeongjang Appearance: Brown hair, brown eyes Personality: Very mischievous Ability: Encyclopedia (Gains vast knowledge when used) Features: Member of the Mystery Investigation Unit. Cookie lover. Deokgae's mentor.

Rank: Lieutenant Gender: Female Age: 26 Aliases: Lt. Sleepground, Sleepground-gyeongwi Appearance: Brown ponytail, grey eyes Personality: Charismatic but occasionally mischievous Ability: Profiling (Eyes turn blue and the crime scene is reconstructed when used) Features: Leader of the Mystery Investigation Unit. A close older sister figure to Radeur since childhood.

Rank: Inspector Gender: Male Age: 28 Aliases: Insp. Suhyun, Suhyun-gyeongsa Appearance: Black short hair, amber eyes, rabbit ears Personality: Kind and calm. Extremely scary when angry Ability: Eloquence (Can tell if the opponent's words are true or false) Features: Member of the Mystery Investigation Unit. Rabbit beastman.