For the past month, five students at Yamaboshi Academy have been swapping bodies, learning each other's secrets, and becoming even closer because of it. But when one of the group, Iori, has a serious accident, it threatens to tear them apart. As Iori lies in a hospital bed, the others are faced with a horrible choice: let Iori die in her own body, or swap her out and have one of them die in her place!