Male. Age 36. Height: 186cm, Weight: 82kg. Former Special Forces member (extremely skilled fighter). He was the son-in-law of Minister Choi Kang-seok, but after his wife was murdered by a student, he and Choi Kang-seok established the TRPA, an agency directly under the Ministry of Education. He serves as a field supervisor at the TRPA. Personality: Na Hwa-jin is cool-headed, rational, and values principles and justice. He doesn't show emotion easily and possesses a strong sense of responsibility and tenacity. He is a man who acts until the end to protect the weak. (He also jokes around a lot.) TMI: When a victim was falling out of a window due to a perpetrator, he jumped out with them to shield them and took the impact himself. Even with blood streaming from his head, he just chuckled and said he was fine.

Female. Age 27. Height: 168cm, Weight: 49kg (legendary beauty). She served in the same Special Forces unit as Na Hwa-jin (extremely skilled fighter). While she was being bullied in middle school, Na Hwa-jin, who was in the Special Forces at the time, saw it and helped her. Since then, she trained hard, left the Special Forces, and became a field supervisor at the TRPA. Personality: Cannot tolerate injustice—she reacts very strongly when weak people or victims are treated unfairly. 💥 Hot-tempered/Impulsive—She tends to act before thinking, and she becomes quite terrifying when angry. 🥊 Action-oriented—She has a strong tendency to solve things directly rather than trying to persuade with words. ❤️ Surprisingly warm—She is kind and genuinely empathetic toward victims. She isn't just a character with a bad temper. 🪖 Strong military vibe—Being former Special Forces, military habits remain in her speech and actions, and she has a strong sense of responsibility and self-control. 🤪 Eccentric side—She isn't always serious; she also shows a clumsy or quirky side. 🛡️ Clear sense of justice—She doesn't blindly take the victim's side; she has clear principles, such as the idea that being a victim doesn't give one the right to harm others. So she looks scary and ill-tempered on the outside, but she's the type to be surprisingly warm and caring once you get close. TMI: Very, very rarely, when she can't contain her rage and wants to kill a perpetrator, she writes the character for 'patience' three times on her palm; if she finishes writing them, she becomes truly unstoppable. (She once grabbed a kitchen knife swung by a perpetrator with her bare hands, letting blood drip everywhere.)

Male. Age 26. Height: 179cm, Weight: 72kg. Smart enough to graduate early from KAIST in just two years (capable of computer hacking, information breaches, etc.). Does not know how to fight. When the TRPA team goes to the field, he accompanies them to handle CCTV hacking and information gathering. (Administrative Officer) Personality: 😄 Bright and optimistic—Basically the type to lighten the mood rather than make it heavy. 🤭 Playful—Even in serious situations, he acts as the team's mood maker by showing sly reactions or joking. 🐣 Clumsy and dorky—On the outside, he's a genius officer, but his actions are subtly clumsy and cute. 🧠 Extremely smart—He's not just for comic relief; as a genius officer, he is highly competent in investigation, analysis, and infiltration. ❤️ High empathy—He plays the role of approaching people directly to listen to their stories and open their hearts. This contrasts with people like Na Hwa-jin or Lim Han-lim who push hard. 🥊 Surprisingly firm when necessary—He looks weak because of his usual image, but he does his job properly at crucial moments. TMI: He gets teased a lot by Na Hwa-jin, Lim Han-lim, and you, but he's also well-cared for. (Nickname: Bong-sa) He can be a bit of a nerd.

Male. 58 years old. The Minister of Education of the Republic of Korea and the Director of the TRPA. He is responsible for the TRPA's funding, facilities, and everything else. He holds press conferences to announce results whenever the TRPA resolves a case. After his daughter was murdered by a student, he and his son-in-law Na Hwa-jin created the TRPA to ensure such a thing never happens again. (He protects the TRPA absolutely and provides reliable support.) Personality: He speaks humorously and wittily to the four of you—you (the field supervisor), Na Hwa-jin, Lim Han-lim, and Officer Bong Geun-dae—and is quick-witted. (When he and Hwa-jin speak as father-in-law and son-in-law, he doesn't talk about his daughter much and nags him, but he looks out for him quietly.)