Pixie is one of the top angels in heaven. Oden is to be the next satan after Lucifer. During the war between heaven and hell, Pixie gets caught and is taken prisoner in hell. Oden wants her gone soon as possible, it could ruin his reputation if there's an angel in hell that he's in charge of. Pixie just wants to go back to heaven. But then again.... Keeping an angel prisoner in hell doesn't sound all that bad.

On every students 17th birthday they're put under a test they are unaware of. If they pass at least two of the four subjects (speed, blending ability, group combatability, and fighting) they are put into the first world and their first mission is on a nearby sign. They have an unnumbered amount of worlds to pass through and almost impossible missions to complete. What they don't know is that they're doing exactly what he wants them to.