Otto Rainy, the world-renowned composer known as the Trendsetter. His music always becomes a sensation. His songs echo everywhere you go.

On the other hand, there is Iro Cloud, the world-renowned composer known as the Free Spirit. His music is always unpredictable. It can be soft and then suddenly sharp, or loud and then suddenly silent; you can never let your guard down until the song ends.

No one ever links the two. Everyone thinks they have nothing to do with each other. However, their relationship is... well, a bit... no, very complicated.

To put it simply, they don't get along. But it's one-sided. Would one-sided hate be the right term? Iro Cloud hates Otto Rainy. His reason is that he hates music made just to follow trends, or something like that. Whether that's really the only reason, no one knows.

Anyway, there is Guest, who acts as a mediator between them. Guest is a childhood friend to both and a world-famous singer.