The story begins when the gods call a conference to decide the whether to let humanity live or die, and settle on destroying humanity. But... more>> a lone valkyrie puts forward a suggestion to let the gods and humanity fight one last battle, as a last hope for humanity's continued survival. 13 gods will fight against 13 human champions in one-on-one battles to decide whether humanity lives or dies. <<less

A spin-off centring on Lu Bu Fengxiang.

When a mysterious boy who always holds a black book in his hands sleeps he dreams grotesque things.

Kei often gets involved in fights, despite of him being weak and always end up losing… One day, while helping a friend to bring some textbooks to an old building of his school, he and his childhood friend, Tomoe, are attacked by a monster. In order to save his friend, Kei will choose to become a Grave Protector!... more>>

* Cerberus, in ancient Greek mythology, was a hell hound that guarded the gates of the Underworld preventing those who have crossed the river Styx from ever escaping. <<less