About the Hour of the Zombie Manga Volume 8

Students are suddenly turning into frenzied zombies, attacking and gorging themselves upon each other's flesh. The school is being torn apart until suddenly...they stop. With the zombies apparently back to normal, the school is now divided between the previously turned and the unbitten. But how long will this peace last? And what caused students to turn in the first place? When any of your classmates could suddenly decide to have you for lunch, a friendly face can become the scariest thing in the room.