Having awoken in the Water Moon Dungeon as a Skeleton after being consumed by a dragon, Rentt has finally obtained a body with some flesh on it, all thanks to the phenomenon known as Existential Evolution. When he returns to investigate an uncharted path within the labyrinth, however, a magic circle trap is set off, teleporting Rentt to an unfamiliar place. The room he finds himself in is none other than the deepest part of the dungeon--the boss chamber.

Who will win? A Giant Skeleton powered by the very energies of the labyrinth itself, or a Ghoul with the experience and weapons of an adventurer? Amidst this intense battle, Rentt feels an overwhelming sensation taking over...