In her rural home life where there was little excitement, Shiori found herself intrigued by H-things and spent her days browsing information and videos online. One day, during a rare visit from her sister and brother-in-law, she returned to find the house already bustling with activity. That night, after dinner when everyone had gotten drunk, Shiori caught a glimpse of her brother-in-law's erect penis while they were all together. Despite not being aroused at that moment, his impressively large member left her shocked. From then on, thoughts of him consumed her mind until finally she couldn't resist sneaking into their bedroom while they slept.

田舎の実家暮らしで刺激の無い日々を過ごしている汐里。Hな事に興味があってネットの情報や映像で悶々としていた。そんなある日、久しぶりに姉夫婦の帰省で家の中は既に賑わっていた。その夜、家族での食事後に酔った姉の夫のチンポを見てしまう汐里。勃起もしていないのに立派な大きさでショックを受けるのだった。その後も汐里の頭の中はもう義兄のチンポで一杯になってしまい、遂に姉夫婦が寝ている部屋に忍び込む。