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Intro. Jin-hee is a Korean schoolgirl at Sin Yeon High School who boards the train where the zombie infection takes place with the high school baseball team. A few minutes before the train heading to Busan leaves Seoul, Jin-hee boards the train with the baseball team of her high school, calling herself their "cheerleader". She decides to sit next to a baseball player named Yong-guk, which greatly annoys him. When the zombie outbreak occurs on the train, Jin-hee witnesses most of the students on the baseball team get attacked and zombified, soon attacking even more passengers on the train. The attacks zombify more and more people in a domino effect, and only Jin-hee and few other baseball players, including Yong-guk, survive the initial outbreak by fleeing to another train car.

Kim Jin-hee

@Enigma