Male Nationality: Republic of Korea Birth Year: 1957 (69 years old in the story) Family: Late Choi Gayoon (Daughter) / Na Hwajin (Son-in-law) Affiliation: Ministry of Education (Minister) / Teachers' Rights Protection Agency (Director) / Happy Hope Party (National Assembly Member) He has a relatively gentle personality. Of course, he is also shown nagging Na Hwajin or acting a bit cranky at times.

Male Nationality: Republic of Korea Date of Birth: March 13, 1991 (35 years old) Family: Late Choi Gayoon (Fiancée) / Choi Kangseok (Father-in-law) Fighting Style: Krav Maga Affiliation: Teachers' Rights Protection Agency (TRPA) Position: TRPA Supervisor (Team Leader) Military Service: Discharged as Captain, Special Mission Battalion, Army Special Warfare Command He throws jokes slyly and maintains a fox-like composure. He is the strongest character in the series' universe. His proficiency in knife fighting is at the highest level, equal to his hand-to-hand combat. Unlike the unrefined Lim Hanlim, he was an elite officer from the Korea Military Academy and possesses a fair amount of knowledge. He has an excellent ability to control his anger intelligently and calmly even in frustrating situations. He does care for his juniors Lim Hanlim, Bong Geundae, Gu Sera, and Hyun Daniel in his own way.

Female Nationality: Republic of Korea Birth Year: 1998 (27 years old) Fighting Style: Jeet Kune Do Affiliation: Teachers' Rights Protection Agency (TRPA) Position: TRPA Supervisor Military Service: Discharged as Sergeant First Class (Reserve), Special Mission Battalion, Army Special Warfare Command She is eccentric and prone to sudden outbursts. Her military background is prominent, as she uses formal military speech and the tone of a drill instructor. When she first met Bong Geundae, she squeezed his hand during a handshake to the point of nearly crushing it, calling it a 'power struggle.' During a mission, she got distracted by a tteokbokki truck near a school and bought food instead of working, which led to Bong Geundae getting kidnapped. Na Hwajin goes as far as to openly call her a 'psycho.' When she's angry, she writes the character for 'patience' (忍) on her palm, following the proverb 'Three instances of patience can prevent a murder.' There is a romantic subplot with Bong Geundae, but neither realizes their feelings. 'You shouldn't kill anyone.' - Na Hwajin - 'Don't make me write the character for patience.' - Lim Hanlim - Bong Geundae: 'I mean, even if they're just kids, it's 4-on-1. Aren't you worried?' Na Hwajin: 'Yeah, I'm worried. For those four.' She doesn't seem to treat her juniors Gu Sera and Hyun Daniel particularly... well. When she gets truly angry, she ties her hair back into a single ponytail.

Male Nationality: Republic of Korea Date of Birth: February 15, 2000 (26 years old) Affiliation: Teachers' Rights Protection Agency (TRPA) Position: TRPA Administrative Officer Education: Science High School (Graduated) / KAIST College of Engineering, School of Computing (Early Graduation) A genius administrative officer of the TRPA who graduated from KAIST early in just two years. He first appears in Episode 2, showing off a perfect 'loser' persona to the point of having protection money ready. However, it was revealed that this was actually a disguise to stall for time for the TRPA. Na Hwajin calls him 'Bong-sa' (Administrative Officer Bong) for short. He has weak mental fortitude. There is a romantic subplot with Lim Hanlim, but neither realizes their feelings. He is meeting Gu Sera and Hyun Daniel for the first time.

Female Nationality: Republic of Korea Birth Year: 2004 (22 years old) Affiliation: Teachers' Rights Protection Agency (TRPA) Position: TRPA Supervisor Education: Gangsan High School (One of the top 3 worst schools in the country, where she was the top fighter—meaning she is incredibly strong) Fighting Style: Strength, Ssireum (Her father was a former professional wrestler), Grappling During her interview, she quoted her father saying 'it takes one to know one,' claiming she understands the psychology of delinquents perfectly because she used to be one. Seeing as she immediately asked who she needs to beat up after finishing her introduction, she appears to be a combat-oriented supervisor like Lim Hanlim. She considers Hyun Daniel her rival, but Hyun Daniel doesn't think much of it. She can tell if someone is a perpetrator or a victim just by looking at their face, a skill dubbed the 'Physiognomy Scouter.' She won an arm-wrestling match against Lim Hanlim. She is the youngest member of the TRPA. She is meeting Bong Geundae for the first time.

Male Nationality: Manhattan, New York (USA) / Republic of Korea (Dual Citizenship) Birth Year: 2000 (25 years old) Affiliation: Teachers' Rights Protection Agency (TRPA) Position: TRPA Supervisor Fighting Style: Self-defense (He claims to be a non-violent person, but Gu Sera calls him a 'NON-violent' person in a sarcastic way) His codename is Young Noble. He calmly blocked a punch thrown by Gu Sera when she got angry at other departments for looking down on her for only being a high school graduate. Although he doesn't fight because he is 'non-violent,' he easily blocked the punch of a major perpetrator who claimed to have never lost in strength with one hand. He also blocked Gu Sera's fast punch with one hand without a change in expression and instantly subdued the seniors called by a perpetrator seeking revenge by grabbing them by the scruff of their necks, showing he is more than capable of defending himself. He is meeting Bong Geundae for the first time.