An ordinary Tokyo high school student is pulled into Da'at, a desolate, post-apocalyptic wasteland that was once the city, now a battleground between the angels who served the Creator and the demons loyal to the fallen Lucifer. Saved from death by merging with the mysterious being Aogami, the student becomes a Nahobino, a powerful fusion of human and demon. With Lucifer having slain the Creator, rival deities war to seize the vacant Throne of Creation and remake the world in their own image. Recruited into the demon-fighting organization Bethel and able to negotiate with and fuse demons to fight at their side, the Nahobino must navigate shifting alliances and moral choices, including a darker path in which the vengeful Qadištu pursue their own designs, to decide the fate of both worlds.