Bathing with the younger sister in school swimsuits! The younger sister's bulge has grown up before you know it, and you can't resist getting an erection! I thought I was not interested in her childish younger sister at home, but one day, she invaded my bathroom! One day, she came to me with a swimsuit and told me she was going to wash my back! She never said such a thing to me.... It seems that she is a friend... (突然、妹がスク水を著てお風呂に亂入！背中を流すと言ってきた！？どうやら夏の新作水著が目當てのゴマすりみたいだけど、妹は偶然なのかわざとなのか胸を押し當てて體を洗ってくる！普段は子供っぽいと思っていたのにスク水姿で密著され思わず興奮！ヤバイと思っても股間はフル勃起狀態で當然妹にバレてしまったが…目を反らしていた妹はチラチラと勃起チ○ポを見て…我慢できなくなった妹は自ら勃起チ○ポに手を伸ばしてきた！！※ 配信方法によって収録內容が異なる場合があります。)