As he struggled through his studies in Tokyo, our protagonist found himself living with the kind and beautiful Yui-san, a married woman whose husband owned the house where he was staying. Despite their close relationship, she always treated him with care and affection. Our young man couldn't help but fall in love with her, chasing after the swell of her breasts every day. However, when it became clear that he had failed his exams and would have to return home to take over the family business, he knew this might be his last chance to experience the passionate embrace of the alluring Mrs. Yui...

受験のため上京して浪人中のその青年は「親戚の叔父の知り合い」的なご関係にあたる、東京近郊の波多野さん夫婦のお宅で下宿生活を送っていた。美人で優しい「下宿先の人妻ユイさん」は、そんな浪人青年に対して毎日かいがいしくお世話をしてくれていた。そんな結衣さんに恋心を抱いていた青年は、毎日悶々と、人妻の膨らみをむなしく追いかけていた。その年の冬に受験失敗が確定し、彼は家業を継ぐため、田舎へ帰ることになり…。