Saionji Saionji, who took piano classes on a whim, had an indifferent attitude towards music. When he met the genius child Reiji Honda, he was attracted to her and became friends with her. It turns out that she is his neighbor, and the two have been together since childhood. She had never performed before and one day she stepped onto the school stage to accompany the students. An unintentional question after school that day brought the two of them to say goodbye in advance.