年上の夫と結婚して1年。大学生の連れ子・大介を受け入れ、円満な家庭を築いている有紀。だが、妊活中の夫は年齢のせいか淡白で、彼女は密かに満たされぬ欲求を抱えていた。そんな折、夫が半年間の単身赴任へ旅立ってしまい…。大介との2人暮らしが始まるや、「妊活ストレッチを手伝うよ」と身体に触れられる機会が増え戸惑う有紀。しかし、夫の不在で飢えきっていた熟れた肉体は、血気盛んな息子の猛烈なアプローチに抗うことができず…。

Yuki has been married to her older husband for a year. She has welcomed his college-aged son, Daisuke, and they have built a happy family. However, her husband, who is trying to conceive, is rather indifferent due to his age, and she secretly harbors unfulfilled desires. Then, her husband leaves for a six-month assignment away from home… As she begins living alone with Daisuke, Yuki is bewildered by the increasing number of times he touches her body, offering to "help with her fertility stretches." However, her mature body, starved for intimacy during her husband's absence, finds it impossible to resist the passionate advances of her energetic son…