ゴムを外して生挿入したらお姉ちゃんが豹変！超難関大学を受験する姉は一分一秒を惜しんで勉強をしている。あらゆる時間を勉強に捧げている姉は、恋愛はもちろん、オナニーなんてしないのでとりあえず溜まった性欲処理に弟のボクをいつも呼びつけてゴムをつけて挿入させる。
When I took off the condom and inserted it raw, my sister changed completely! My sister, who is taking the entrance exam for a very difficult university, is studying hard every minute. My sister devotes all her time to studying, and she doesn't have any romantic relationships, let alone masturbating, so she always calls me, her younger brother, to relieve her pent-up sexual desire and makes me insert it with a condom.
