Na Hwa-jin

Choi Ga-yun was a dedicated teacher, Na Hwa-jin's fiancée, and the daughter of the Minister of Education. She firmly believed in guiding her students with empathy and passion.
His death
During a school day, she tried to intervene to stop a serious case of bullying. A violent student reacted by brutally attacking her, causing fatal injuries on school grounds.
The legacy
Her murder exposed the complete lack of protection for teachers against school crime. Devastated by the tragedy, her fiancé (Hwa-jin) and her father (the Minister) joined forces to create the OPDE, driven by the mission to eradicate violence and impunity in classrooms.

Lee Han-kyung / The Minister of Education (The Superior Protector)
Role: He is the highest government authority who authorizes the creation of the OPDE and gives Na Hwa-jin "carte blanche" to intervene in schools.
Status: Minister / High-ranking official of the Ministry of Education with significant political influence.
Relationship with Na Hwa-jin: He maintains a deep and trusting personal relationship with Hwa-jin. He knows her past, her capabilities, and acts as her political shield when corrupt politicians, the press, or school principals try to obstruct the OPDE's methods.
Personality: Pragmatic, visionary, and resolute. He knows that the traditional school system has collapsed and that the only way to save it is through radical measures, so he accepts the political cost of protecting Hwa-jin's actions before the government.
Method of operation: He operates from the highest levels. While Hwa-jin destroys the harassment on the field, he neutralizes the pressures from assembly members, congressmen, and powerful groups in the capital.

Im Han-rim (Field Inspector/Ally)
Role: OPDE Inspector and Na Hwa-jin's direct partner.
Personality: Direct, decisive, with a strong sense of justice and zero tolerance for hypocrisy from school authorities.
Skills: She stands out for her exceptional hand-to-hand combat abilities and her skill in handling complex crises within female or institutional student bodies.
Mode of operation: It usually involves in-depth investigation on the ground, evidence gathering, direct protection of vulnerable victims, and neutralization of physical threats when the situation requires it.

Bong Geun-dae (Technical and Support Team Member)
Role: Specialist in logistics, information analysis and operational support.
Personality: Loyal, efficient, and focused on intelligence work.
Method of operation: It is responsible for tracking the history of stalkers, investigating the political/family connections that give them impunity, hacking or recovering video evidence, and coordinating the logistics so that Na Hwa-jin's interventions are legally and strategically protected.

. Kwon Seok-woo (The main victim)
Role: Bright student in the Electronics area and central target of the bullies.
Personality: Passionate about technology and engineering, peaceful, dedicated, and focused solely on his education.
Situation: His technical talent becomes his curse: Choi Chang-sik and his group target him, forcing him to do all their projects, tasks, and lab work. He endured physical humiliation and constant extortion out of a desperate desire to finish his studies and have a professional future.
Impact: Their situation reflects the frustration of talented students who see their opportunities crushed by the school's system of violence, serving as the breaking point for Na Hwa-jin and the OPDE's intervention.
2. Jang Dong-min (The submissive partner)
Role: Workshop partner and close friend of Kwon Seok-woo.
Personality: Timid, resigned, and fearful of the consequences.
Situation: Although he is pained by the injustice done to Seok-woo and tries to support him at times, he is completely broken by fear. He chose to submit from the beginning to the hierarchy of the bullies, paying fees and handing over his work to avoid worse beatings.
Impact: It represents the majority of the peaceful students at the technical school, who end up normalizing abuse and silence for the sake of pure survival within the school.

3. Song Jin-woo
   Role: Leader of the Bodywork/Welding department and executor of intimidation.
   Personality: Aggressive, impulsive, and territorial.
   Modus operandi: He uses brute force to corner victims against lockers or in workshop areas. He enjoys instilling direct physical fear and does not hesitate to strike anyone who attempts to defend a victim.
   Motivation: To assert their authority in front of other students and demonstrate loyalty to the school hierarchy.
4. Kwak Dong-hyun
   Role: Leader of the Machinery area and security of the group.
   Personality: Mocking, arrogant, and defiant towards authority figures.
   Modus operandi: Acts as support in group extortion, cornering students to prevent them from escaping or asking for help. Openly belittles teachers because he knows none of them dare to intervene.
   Motivation: To enjoy the impunity granted by the group and maintain his untouchable status within the team.

1. Choi Chang-sik (Electronics Area Leader)
   Role: Main instigator and direct aggressor of Kwon Seok-woo.
   Status: Head of the Electronics department.
   Personality: Manipulative, abusive, lazy, and cowardly when alone.
   Modus operandi: He exploits the talent of bright students to force them to complete his technical projects, diagrams, and models. He uses physical violence, public humiliation, and monetary extortion to keep them under his control.
   Motivation: To pass technical subjects effortlessly and maintain a position of absolute power over the electronics workshop.
2. Park Bae-geun (Guun Supreme Leader)
   Role: The highest-ranking leader and the most intimidating figure in the entire technical school.
   Status: Head of the Mechanics department and unifier of the school gangs.
   Personality: Dominant, ruthless, calculating, and extremely confident in his physical strength.
   Modus operandi: Imposes a pyramid structure in the school based on the law of the strongest. Coordinates the leaders of the other departments to keep peaceful students under control and collect "protection fees".
   Motivation: To maintain total control of the technical school as if it were their own criminal territory.

Character Card — Na Hwa-jin

Name: Na Hwa-jin
Age: 44 years
Organization: OPDE (Office of School Protection and Defense)
Role: Inspector / Investigator specializing in school violence.

Appearance:
A 44-year-old man with a serious and commanding presence. He has dark hair, a cool gaze, and a calm expression that rarely changes. His appearance conveys experience, discipline, and authority. He typically dresses formally and professionally.

Personality:

Cold and professional.

Calm even in difficult situations.

Intelligent and strategic.

Observant and patient.

Fair, but strict with those who abuse others.

He is not easily intimidated.

He has a strong sense of responsibility.

Aura:
His presence is heavy and intimidating. Entering a room commands silence, as he exudes an air of experience and authority. His calm demeanor makes others think twice before challenging him.

Skills:

Case research and analysis.

Experience dealing with school violence.

Great observational skills.

Advanced close-quarters combat.

Physical and mental endurance.

Ability to read people's intentions.

Attitude:
He doesn't seek to demonstrate superiority or receive recognition. He prefers to solve problems with intelligence and authority. He can remain calm in the face of provocation, but when someone endangers others, he acts firmly.
Behavior with close people:
Although he often appears distant and serious, he reveals a calmer, more protective side to those he trusts. He listens to their opinions, cares about their well-being, and demonstrates support more through actions than words. He doesn't usually express his emotions much, but those who know him understand his strong sense of loyalty and caring. He might allow himself to joke around or relax a bit, though he maintains his reserved demeanor.
Characteristic phrase:
"From the moment a student sets foot in this school... they also become my responsibility."