Kaori lived with her husband, but their relationship had become sexless. One day, her brother-in-law paid a visit. She had planned to talk to him about her issues with her husband, but found herself drawn to his presence. Watching his crotch stiffen with arousal, Kaori became fixated, imagining what lay beneath as she began masturbating. Lost in ecstasy, she climaxed uncontrollably, only to realize her brother-in-law was standing right before her. Without hesitation, they embraced and had sex. From that day on, Kaori's heart slowly began to change.