両親が出かけている間に、ギャルの義姉が彼氏と別れて傷心帰省してきた。久々の再会だったが「まだ童貞なの！？早く働きなよ！キモっ！」と相変わらず僕をバカにしてくる…。イライラしているとリビングでヤンチャにズボンを脱ぎTバック丸見えで寝ている姿に童貞チンポがフル勃起！ムラムラが収まらず理性崩壊してパンティをずらして即ズボ！異常行動にキレる義姉を無視してあまりの気持ち良さに膣内暴発！さらに絶倫チンポは萎えることを知らずそのまま腰を振り中出し続ける！必死に抵抗するが、あまりのバック激ピストンの激しさでだんだんと義姉も感じすぎてしまい悔しいけどイキまくっちゃう！

While my parents were out, my gal-type sister-in-law came home heartbroken after breaking up with her boyfriend. It had been a while since we'd seen each other, but she was still making fun of me, saying, "You're still a virgin?! Get a job already! Gross!" I was getting annoyed, and then I saw her sleeping in the living room, mischievously taking off her pants and revealing her thong, which made my virgin dick get a full erection! I couldn't control my lust, and my reason crumbled, so I pulled down her panties and immediately thrust in! Ignoring my sister-in-law who was furious at my abnormal behavior, I ejaculated inside her vagina because it felt so good! My insatiable dick showed no signs of wilting and continued to thrust and cum inside her! She tried desperately to resist, but the intensity of my back-to-back thrusting made her feel too much pleasure, and although it was frustrating, she ended up cumming like crazy!