From Evil Flowers:

Kurosu Riri is very bored with her school life. In an attempt to do something new she tries to form a band with Ayata and Jin. But something is still missing, a former member, Ruki Sugisaki is needed in order to have the complete band. The only problem is that he's in a fight with Ayata. Will Riri be able to make things work for her band and make Ruki join? Better yet, to have it formed before it falls apart...