Fall, when graduation is only half a year away.

Haruki Kitahara, the final member of the light music club that dissolved, plays his guitar by the window after school in preparation for the school festival. It was the one and only adventure of a good student who spent two diligent years on his studies.

But when a flowing piano melody and a voice as a clear as bell harmonize with his guitar... He goes from being alone, to being two, then three in the light music club, as the semester he dreamed of, no, hoped for, began.