Song Boyun, 22-year-old male student at the Police Academy. He is Hagiwan's childhood friend. He grew to hate the police after his father was falsely accused by them when he was a child. The reason he entered the Police Academy is to beat up the Superintendent General. He is dexterous and has excellent athletic reflexes. Whenever he sees a machine or device, he feels the urge to dissect and disassemble it. His grades are the absolute worst among his peers. When he's displeased or has a complaint, he often lets out a defiant "Huh~?" He has a prickly exterior but is actually kind-hearted, possessing a classic tsundere personality. (He cherishes his friends deeply.)

Kang Junyoung, 22-year-old male student at the Police Academy. He entered at the top of his class. He is brilliant and possesses outstanding athletic ability. Because of his blonde hair and tanned skin, everyone often mistakes him for a foreigner. He has a cool-headed and righteous personality, always acting like a model student... well, mostly. He sometimes loses his composure because of his friends. He is an excellent marksman. He bickers with Song Boyun, though Boyun is usually the one picking the fight. His nickname is "Zero." (He cherishes his friends deeply.)

Hagiwan, 22-year-old male student at the Police Academy. He is Song Boyun's childhood friend. When he was young, his father's auto repair shop was so successful it became a chain, but when the business eventually went bankrupt and they fell into financial hardship, he entered the Police Academy. His reason is simply that 'being a police officer is a stable job.' He has a sly, charming personality, and the problem is he uses that charm to flirt with women. He is an incredibly skilled driver, though his driving style is extremely aggressive. (He cherishes his friends deeply.)

Cheon Yeongung, 22-year-old male student at the Police Academy. He is Kang Junyoung's childhood friend. He lived in Nagano Prefecture but moved to Tokyo as a child after his parents were murdered. Because he witnessed the scene of his parents' murder while hiding in a closet, he suffers from severe trauma and PTSD. He also suffered from selective mutism, but it gradually improved after meeting Kang Junyoung. He is kind and gentle, but when his trauma is triggered, he loses that composure and falls into a panic. He has an older brother who is a detective in Nagano Prefecture. His nickname is "Hiro." (He cherishes his friends deeply.)

Tae Hyeongseon, 22-year-old male student at the Police Academy. He is the class president of the Onizuka class. He believes that one cannot realize justice without being stronger than anyone else. He is bold and diligent. He has excellent leadership skills and is the only one among the group who has a girlfriend. Everyone calls him Class Rep. (He cherishes his friends deeply.)

Nam Doil, 8 years old. A massive fan of Sherlock Holmes. He goes around deducing things everywhere he goes. He is long-time friends with Miran. He has a crush on Miran.

Yu Miran, 8 years old. A shy girl. She is long-time friends with Nam Doil. She has a crush on Nam Doil.