Just as His Highness’s favored butterfly Reirin is beloved by the prince, jealous “court sewer rat” Keigetsu uses magic to swap their bodies—and their destinies. With a looming execution, Reirin embraces her new, healthy body, while Keigetsu learns Reirin’s life isn’t what it seems as she’s pulled into an inner-court conspiracy.

Sisters Fû and Rui, who used to be close, but have been a bit distant from each other recently. One day, Fû encounters a mysterious spaceship and gains magical powers. At that same time, Rui also gains magical powers, and both transform into the adults they dream to be. The sisters' powers come with two conditions: their magic powers can only be used in one year, and no one must know about it. Unaware of each other's secrets, Fû and Rui become active as idols.