Catherine, a sorceress, leads her mercenary group on a mission into the mysterious Doden Mountains.

In the corner city built by the elven outcasts, due to the resonance of miracle magic, a spatial door to the land of successive seals was opened. Catherine and Deputy Leader Ace are unexpectedly captured by the Devil of Hell, the servant of the Demon King of Hell, into the Sealed Land in the depths of the Underworld.

There, the two of them were about to become sacrifices to the Great Demon King, and the history of the continent was changed.