私、見ちゃったんです…お兄ちゃんがえっちな本片手に一生懸命おちんちんを擦っているのを。あのとき見た大きく腫れたちんちんが忘れられなくなりました―性に目覚めた妹が、お兄ちゃんを相手にせっくすしてみたいとお願いされたあの日からー両親の不在中を狙って、家中のいろんなところでSEXしまくる関係に。まだ、性の知識が不十分でゴムもつけずに、中にも出してしまう…早く大人になりたくて、妹と汗だくでヤリまくったあの夏の日。

I saw it… my brother was frantically rubbing his penis with a dirty book in his hand. I can't forget the big, swollen penis I saw that day—from the day my sexually awakened sister asked me if she could have sex with her brother—we started having sex all over the house whenever our parents were out. I still didn't have enough sexual knowledge, so I didn't use a condom and I came inside her… I wanted to grow up quickly, so I had sex with my sister all sweaty that summer.