When the Chaos Cult summoned the God of Destruction, Magu Menueku, years ago, a battle of epic proportions ensued, with humanity's fate in the balance. To save mankind, the noble Holy Knights sealed Magu in a Holy Sealing Crystal. Time passed, and one day, Ruru Miyanagi, an exuberant middle schooler, discovered the crystal while digging for clams. Unwittingly, she freed Magu from his long slumber. Despite this, Ruru was undaunted and even bestowed the moniker of "Magu-chan" upon the formerly fearsome deity. Magu must rely upon Ruru to help him regain his full power and ominous form. Despite their odd pairing, their friendship grows as Magu learns more about the underwhelming world that he plans to destroy.