Terrifying demons threatened humanity's existence eight hundred years ago. Humans were on the verge of extinction when they pleaded to their gods for help. Battle deities called as "Idaten" sprang from these frantic prayers for redemption. The Idaten, who possessed incredible strength and endurance, defeated the demons, ushering in a period of exceptional calm. The current generation of Idaten is unaware of the demon's savagery since they have never faced one. Instead, they have led a tranquil existence. Training under Rin, the only surviving Idaten from 800 years ago, the new Idaten find means to survive at a period when they appear to have outlived their purpose. When the oppressive Zoble Empire resurrects a demon, however, the misfit crop of gods are called to the battlefield against their natural enemy once more.