Tajika Kouhei

He awoke in a cold and rustic room. There were only a door and torture devices inside of it. While he could not yet grasp the situation, a number rose to the surface on the back of his right hand. "I know your pain." The young man figured out that pain and the door were linked, and so he could only endure his own suffering.

A horrifying competition for survival between normal high-school students soon becomes filled for blood, guts, and death!