In the sexless days that have continued since her husband became an erectile dysfunction two years ago, Rei was inviting frustration. And when patience has reached its limit, Rei witnesses her son's masturbation scene. Reiki who is deprived of calm judgment in Musuko, a son who is eagerly aroused, will seduce her son. Although Ataru is also puzzled, it does not resist the incenses of adults released by Reina, and the two will be connected. ... However, in order to finish the forbidden relationship with one mistake, too much sexual desire was strong and my son was mad. And the flesh of two who opened the forbidden doors will escalate to further forbidden areas ....2年前に夫が勃起不全になって以来続くセックスレスの日々に、れいなは欲求不満を募らせていた。そして我慢も限界を迎えた時、れいなは息子のアタルのオナニー現場を目撃してしまう。立派にそそり勃つ息子のムスコに冷静な判断力を奪われてしまったれいなは、あろうことか息子を誘惑する。アタルも戸惑いつつも、れいなが放つ大人の色香に抗えず、二人は関係を結んでしまう。…だが、禁断の関係を一度の過ちで済ますには、あまりにれいなの性欲は強く、息子は絶倫だった。そして、禁断の扉を開けてしまった二人の肉欲は、さらなる禁断の領域へとエスカレートしていく…。