One day, while playing baseball, an ordinary boy, Manta Okaruto, meets a boy named Zonbee who came from the demon world to the human world. He is a zombie, demonstrating immortality that humans cannot match, scattering his internal organs and brains, terrifying humans including Manta. However, Manta becomes friends with Zonbe and invites him into his house. This is the beginning of the fun and grotesque everyday life of Manta and Zonbei.