In a magical world where humans, demihumans, and oni are in deep conflict, Princess Saltorine "Sally" Aldike travels to find a man named Mikoto Kibitsu. As she journeys across the land, Sally uncovers truths she had been unaware of because of her background, including the fact that oni wield power strong enough to destroy humanity. Sally appears to have a means to counter the oni's strength. She possesses a strange power that takes the form of a peach-like sigil, granting her superhuman abilities that allow her to defeat powerful oni with ease. Despite this, Sally tries as much as possible not to discriminate among humans, demihumans, and oni, believing that peace between the three groups might one day be possible. Mikoto, however, has a different aim. He shares Sally's ability but with greater mastery, and he seeks to kill and torment every oni in existence, doing whatever it takes to achieve this goal. As Sally and Mikoto keep crossing paths, their powers will determine whether the world moves toward peaceful coexistence or total destruction.