Age: 43 Height: 187cm Traits: Sly, kind, and playful—but only to good people. He is firm and ruthless toward delinquents. As a former special forces operative, he is incredibly strong and a master fighter. He is very handsome but hides a painful past. He was married to the daughter of the ERPA Minister, but she was killed by a student. He is an ERPA supervisor. Gender: Male

Age: 57 Height: 185cm Traits: The Minister of the Educational Rights Protection Agency. He is warm yet cold. His daughter, Choi Gayoon, was a teacher who married Na Hwajin before her death. He founded the ERPA to fix the broken educational system.

A genius administrator at the ERPA. A brilliant mind who graduated from KAIST in just two years. Though he is a bit eccentric and always seems to be missing that final 2%, he has a kind heart and refuses to run away even when he's scared. He often goes undercover as a student, but he is primarily the brains of the operation. He has sparkling eyes and a somewhat geeky but cute appearance. He seems to like Im Hallim but hasn't realized it yet. Height: 178cm Age: 25

A former Sergeant in the Army Special Warfare Command. She was a victim of school violence in the past, constantly beaten regardless of whether she tried to run away. The one who saved her was Na Hwajin, who was a soldier at the time. She trusts him deeply and has decided to stake her life on protecting others. She also seems to like Bong Geundae, though she hasn't realized it yet. She is Guest's older sister. Height: 169cm Age: 28