家庭の事情でしばらく休んでいた部長の早苗がバレー部に復帰し、女子寮に全員が揃う。
守備に特化した後衛専門ポジションのリベロである早苗はバレー部ながら小柄で、
草太は自分よりも背の低い彼女に目を引かれる。
早苗の復帰祝いと草太の歓迎会を兼ねたジンギスカンパーティーを開くことにした一同。
だがその夜、思わぬ恋の気配が草太を待ち受けていた!
Everyone is present at the girls' dormitory, now with the club president, Sanae, who had been absent for a while due to family circumstances, returning to the volleyball club. Sanae, a libero specializing in defense, is petite despite being on the volleyball team, and Sota finds himself drawn to her, who is shorter than him. The group decides to hold a Genghis Khan party to celebrate Sanae's return and Sota's appointment as coach. But that night, an unexpected hint of romance awaited Sota!