Ookii Onnanoko wa Suki desu ka?

Tall Kaori and short Sota are siblings by marriage. One day, commanded by Kaori, Sota becomes the dorm manager and coach for her university women's volleyball team. Among the members is Ayano, his first love, and they have an unexpected reunion! Sota begins living together with the club members as the dorm manager. But that night, he witnesses an unexpected side of Ayano, whom he's always admired...?!