Nosaki Ritsu is a Production Manager at Grace Design Office, a fashion design company, when Head fashion designer Kousaka Seiji asks him to be a butt-model for his underwear clothing line.

Jinu is a weak coward left in a world full of zombies, ruled by survival of the fittest. Then, there are those other survivors who would use him, or perhaps even protect him. In the midst of survivors fighti...