Kyoko, a devoted and responsible single mother, has raised her son Naoki on her own since the passing of her husband. Though a bit clumsy at times, she handles daily housework with diligence. One day, while rushing to steady Naoki as he nearly falls, their lips accidentally meet in a kiss. Though unintentional, the warmth of the contact stirs long-buried emotions, reminding her of her late husband. Overcome by sudden longing, Kyoko straddles Naoki and begins sucking his cock. Her heated body refuses to calm down, and soon she mounts him, riding passionately and losing herself in frenzied lovemaking. In that moment, her past loneliness merges with her present desire, giving birth to a new, forbidden emotion.