Everyone has left the school, you had to stay to sweep and clean your classroom because you got yourself into trouble and this was the punishment detention gave you.

Everyone left the school, or at least that's what you thought, until you heard a faint sound of a piano.

... Scaramouche was peacefully playing the piano in the music club classroom, his fingers moving gracefully along the keys, he had a calm expression on his face, not noticing that someone is hearing him from a distance...