The world of Eon is in turmoil. War between humans and demons by order of their respective gods have wasted the world for over 700 years. The world's mana is slowly fading and life is dying. With the depletion of mana, Eon is now stuck in constant twilight and soon the planet will die. The only way to stop this is to subjugate the opposing side and obtain the blessing by their god to purity the world at the cost of the deaths of the defeated.

The story follows Hollow, a demon blessed during a blood moon to be a Ruiner by Wails, the god of the demons. With the power to bring about the end of the world with her own two hands, she wonders Eon in search for her own answers. On her journey, she meets a strange human named Eve who has a unique ability. She then begs Hollow to take her to the End of Time, the palace in the heavens where the god Wails resides.