Yukiko is a young wife who is feeling lonely and unsatisfied. Her husband Koichi won't satisfy her needs, and in fact they sleep on separate beds. To add to her frustration Yukiko finds some pictures on her husband's cell phone – pictures of an unknown naked woman; also one night she sees her two children – who are not related by blood – together in bed.

Yukiko spends her time at home trying to satisfy her needs on her own. Until one day the father of her husband comes to visit and sees her in compromising situation. That's when things in her family start to change…

(Source: AniDB)