Rina tells the nerdy Nanashi boy to abstain from masturbation until the next assembly.
One day, when he's holding back to the limit, Rina says, "Let me do it right now," and Nanashi's heart skips a beat.
A foursome with Rina, Megu, and Mio in their gym clothes begins, and Nanashi's excitement reaches a fever pitch!
But then the busty teacher Yuuka arrives, and the four of them hurriedly hide in the lockers...?
Peeking at the girls changing from the locker room, he finds himself in a packed train with the girls in their gym clothes!
Nanashi's reason is on the verge of exploding...!
陰キャ男子「ナナシ」に「りな」が突きつける次の集会までのオナ禁生活。
限界まで我慢してたある日、「りな」からの一言「今すぐヤらせろ」で胸キュン。
「りな」「めぐ」「みお」の3人と体操着4Pが始まり「ナナシ」の興奮も大絶頂！
しかしそこで爆乳ボディの「ゆうか」先生がやってきて、4人は慌ててロッカーへ隠れるが…？
ロッカーから生着替えを覗きつつ、体操着のギャル達と満員電車状態！
「ナナシ」の理性は爆発寸前に…！
