The mighty god Zeus is more and more worried about the state various gods are in. They seem to have grown too far from humanity, that they need some help to reconnect. For that reason he creates a school, modeled after human schools – with different dormitories for each gender, a cafeteria with real food, and of course the classrooms.
Kusanagi Yui, an ordinary human girl, just coming back from her own graduation, happens to find a glowing sword in a shed. Curiosity forced her to touch it, which in turn led to her being transported to that very school. There she stumbles upon one god after another, and of course Zeus himself, who explains to her, that she is to teach the gods about humans, life, and love. On top of that he seals every gods powers, and declares, that if they are not able to fill the magical container (probably with knowledge and understanding about humanity) within a year – they will all be trapped on school grounds forever.
In order to cancel the negative effects of the weakening bond between the two worlds, Yui has to give her best to teach the divine the human way.