A thousand years ago, Enka, the god of destruction, died leaving a prophecy that its "child" would one day destroy the world. In order to prevent this, Operation Cozy Family is implemented in which the children who are potentially prophesied as the Child of Enka are suddenly forced to live together and take different familial roles.
This impromptu family contains children, human and otherwise, with an official of the bureau and a self-proclaimed goddess assigned to be the married parents of the household. The goal of Operation Cozy Family is to discern who the prophecy applies to, as well as to teach all of them about the love of family in hopes of convincing the Child of Enka not to destroy the world. But with all families, there's bound to be mishaps, and with this group, there's also an adventure with the fate of the world in the balance.