From the moment she and her fellow students arrive in the mountain village of Yasaka, Mikoto knows that there is something very wrong with this tiny town. Can it really be true that, for 50 years, not a single girl has been born in this isolated community? Despite the fact that Mayor Amano and the other all male residents have enthusiastically welcomed her and the other three coeds attending Professor Ashihara’s overnight seminar, Mikoto can’t shake the sense of increasing dread that consumes her. Something horrible has happened here. Something that is about to happen again. Because the town has been waiting for her. And the other girls. From the pages of the hit online manga published in Web Comic Gamma, the nightmare is about to begin!

They thought they were coming to study a mysterious town hidden in the mountains of Japan. Instead, they’ve discovered that their Professor brought them to Yasaka for a much darker purpose. Now Mikoto and the other girls are trapped in a monstrous nightmare. As the villagers become increasingly more insane, the college students find themselves at the center of arcane rituals focused on blood and rotting flesh. Their only chance is to escape, but their captors are far too numerous and know the lay of the local land far too well.

One day, it's decided that all people with blood type B have to be killed. There are people in black costumes who chase after and kill everyone with blood type B. Tsukasa is one of those people. Together with her friend Yui she tries to stay alive and staying alive means running because hiding isn't a solution. On the hunt, they meet Masaharu and together they decide to fight against those black costumed creatures.