Info from WIKI

Director Lee has shown louse with duties as school director. He was a cowardly, perverted, and selfish man who drank on his job, stalked underage girls, and made racist comments. His true colors were shown even more after the monsters make their debut. On multiple attempts, he attempts to steal Gyuhwan's shotgun for himself, pretending he'll protect others. He also pushed a teacher to his death, having hoped he could save him. He even outright felt relieved that the monsters were attacking other students instead of him.