My girlfriend suspects that I'm cheating on her, so she has put a chastity belt on me. One day, my girlfriend's sister, Rin, comes over because of construction noise keeping her awake. She decides to stay with us for a week... As soon as I see Rin naked after taking a bath, I can't help but get hard! When Rin finds out about my chastity belt, she starts teasing me playfully. Thus begins one week of pizza-making management by the devilish older sister, Rin! "Please let me borrow your breasts, big sis. I can't hold back anymore!"

浮気を疑われボクは同棲している彼女に貞操帯を付けられている。そんなある日、ボクらの家に彼女の姉・凜が工事の騒音が原因で眠れないという理由で1週間限定で一緒に住むことに…。たまたまお風呂上がりの凜を見たボクは思わず勃起！貞操帯が姉・凛にバレてしまった。面白半分ボクの貞操帯を弄り…からの。そんな感じで小悪魔姉・凛の1週間のパイズリ射精管理がスタート！ 「おっぱい貸してくださいお姉さん。もう我慢できません！」