After barely finishing his final assignment, Jung Hohyun, who fell into a deep sleep, wakes up on Christmas morning to blood and flesh being ripped out right in front of his eyes. Some of the students who remained at the school became zombies for an unknown reason. Jung Hohyun, who was in a panic, ran away frantically. He ran into a man, Ki Wonyoung, who kills zombies with no remorse. However, the joy of meeting a decent human is short-lived since this man is somewhat strange. 'What are you talking about? who are you?' 'Fuck you, Hoobae-nim. Why are you suddenly pretending not to know me? It's me, Youngwon. Ki Youngwon.' Jung Hohyun unknowingly falls for this strange guy who is not only pretending to know Hohyun during their first encounter, but also seems only interested in saving him in this unbelievable reality.