薫は自分でデートを勧めておきながら、草太と綾乃がホテルまで行ったことを知ると思わず動揺。
それでも草太の姉としてふたりの間を取り持ってやろうとするのだが…
一方、一連の話を聞いた桜と鏡花それにユリアは
「自分達も綾乃と同じ女子バレーボール部員なのだから同じことをする権利があるはず」
という謎理論を持ち出し、草太への誘惑を開始するのだった！
Kaori, who had suggested the date herself, becomes flustered upon learning that Sota and Ayano went to a hotel. Still, as Sota's sister, she tries to mediate between them... Meanwhile, Sakura, Kyoka, and Yuria, having heard the whole story, come up with a bizarre theory: Since they're also members of the girls' volleyball club like Ayano, they should have the right to do the same thing! And so, they begin seducing Sota!
