Fresh out of an all-boys school, Kou Usuta is thrilled to enter his new co-ed high school. Surrounded by cute freshman and senior girls, his expectations keep on growing. He exchanges numbers with Misa, and they arrange to meet at an out-of-use PE storeroom where the seniors usually hang out. After school, Kou enthuasiastically heads to the PE storeroom, eager to have his first real experience with a girl, but little did he know...