The very best of friends are about to become the worst enemies. When five normal and well-adjusted teens at Yamahoshi Academy form the Cultural Research Club, all is right with the world. The close-knit club of girls and boys are perfectly happy in their daily school life—until a supernatural being known as the Heartseed enters the picture.

Now the lives of the five friends are turned upside down, as they start swapping bodies and minds. Inner secrets, hidden pasts, and dark urges are revealed to one another. Will the Heartseed and his mind-bending powers pull the five friends apart forever?