Long ago a magical cat disguised as a human woman fell in love with a human man. It is said that during their time together they even had children. They say that afterwards, the magical cat dwelt happily as a human, that she ascended to the heavens and became a cat-god, and is even now watching over the world of cats and men. Of those descendants, the cats of Cat Forest Town say that they have mysterious powers. The townsfolk care for the cats as their guardian dieties, and the cats, too, have become attached to the humans.

Hirose Goushi has a huge sister complex. So huge, he moves from his home town to Tokyo to attend Myouzen University in order to escape it! Three years later, Goushi’s little sister Noa shows up and informs him that she’s taking the Myouzen University entrance exam and that she will be moving in if she passed. Little does Goushi know, she has a similarly large (if not larger) brother complex.