From Shoujo-Sense:
Kanamu's favourite time of day is after school, when she meets to practice with her three-person band, "Chocolat no Yell." She may be inexperienced, but she's determined to do well. If only Rito, her senpai in the light music club, weren't always showing up to pick on her. With the band's first live performance coming up, will everything go off without a hitch? And what exactly is Rito's problem, anyway?