The mermaid village of Mildesta is invaded by the evil Onigami forces. The masters and friends of the mermaids attempt to rescue them, but they are captured by the enemy forces. Everyone falls into the enemy trap except for full-haru, who escapes the enemy defenses on his own. The fate of all of them rests on the shoulders of two strange creatures: the "puues" , and the "griff" . The puues are in the middle of a meal when they realize that they have stumbled upon a kitchen. They are called "pues" and "griffs" respectively, and they are confused as to who they really are. They wonder if they are oni or not, and when they discover that they are, they decide to fight.