As a small child, Kazuhi Uesaka had a chance encounter with mysterious twins at a shrine near his grandfather's house. Wishing to see them again, he returned many times to the shrine, but never caught sight of them again.

Six years later, Kazuhi visits the shrine for the first time in a long while, and is reunited with the two standing there as they were back then. Haruka has a bright smile on her face, while Ryo looks more mature. They look the same as they did when they were children, but...