夫と結婚して3年の人妻・美緒。最近は夫と喧嘩ばかりで、夫婦生活に疲れてしまっていた。そんな中、職場であるパーソナルジムで体験にきた井上と出会う。井上は夫と違い、気遣いも、礼儀も、全てが正反対。トレーニングで会う度、美緒は井上に心を開いていった。ある日、美緒は井上に夫の悩みを打ち明けると優しい言葉と抱擁で慰めてくれた。井上の優しさに触れた美緒は、想いを抑えきれず思わず唇を奪ってしまって…。

Mio, a married woman of three years, had been constantly arguing with her husband lately and was growing weary of their married life. It was at the personal training gym where she worked that she met Inoue, who was there for a trial session. Inoue was the complete opposite of her husband—considerate, polite, everything. Each time they met for training, Mio began to open up to Inoue. One day, she confided in Inoue about her troubles with her husband, and he comforted her with kind words and a hug. Touched by Inoue's kindness, Mio couldn't control her feelings and impulsively kissed him…