Kagawa, who had been staying at a friend's house, accidentally saw the disgraceful behavior of his friend's mother, Ayaka (Mashiro An). He had always liked and admired Ayaka, and her lewd appearance left him in a state of turmoil. Determined, he confesses to Ayaka, but as expected, he is rejected. However, Kagawa cannot give up and stubbornly persists. Feeling a passion in Kagawa's sincere feelings that her husband lacks, Ayaka accepts, with the promise of only once...