Dark Edge Volume 1

After his mother's death, Kuro Takagi transfers to Yotsuji Private High School, where his father is the proprietor. The school had a peculiar regulation which stated "students shall not remain on campus after sundown." Breaking the regulation on the first day of attendance, Kuro and his classmates are attacked by zombies that suddenly appear. In fact, they learn that the faculty members and even some missing students are zombies who possess an "evil gene". Kuro and his classmates somehow escape this time, but this was just a prelude to a more bizarre campus life that awaits them.