仕事で忙しい夫がセックスしてくれず欲求不満で悩んでいた「ひかる」。そんなある日、隣に住む既婚の男性と話す機会があり、つい性の悩みを相談してしまう。歯止めが利かず惹かれていく2人。一線を越えた2人は際限なく不倫関係にのめりこんでいく。Hikaru was suffering from frustration because her husband, who was busy with work, did not have sex with her. One day, she has a chance to talk with a married man who lives next door, and she ends up discussing her sexual problems with him. The two are attracted to each other, and without being able to stop themselves, the two cross the line and become involved in an endless adulterous relationship.
