Satou Tatsuki, a class troublemaker, obtains his motorcycle license and takes his genius best friend, Morisawa Kai, for a ride. They are involved in an accident, and Morisawa dies instantly. However, Morisawa wakes up in a hospital inside the body of a girl who was admitted for alcohol poisoning. His relationship with Tatsuki begins to take on a whole new level as he deals with the changes in his body and the other soul inhabiting it.