Toshiharu Sasaki

One day, high-school boy Yamada bumps into the beautiful girl Shiraishi on the stairs (literally), and their lips touch as they fall. When they regain their wits, they realize that they have swapped bodies. As time progresses, the two realize that this is not the only mysterious happening in the school.

Grigio Academy Boarding School. Students who attend this school in two countries and reside in their own dormitories. Inazuka and Persia are rival dormitory leaders, but in secret they love each other. Now, they have to keep their relationship a secret from their dorm mates, or ruined things will happen to them.