Please train me in front of my husband

A few years after marriage...Yumi, a full-time housewife, invites instructor Tamura to her home to hold a cooking class for her wife. One day, after her students returned home, Yumi was alone with Tamura and confessed that she hadn't had sex for a year because her husband was incapacitated. While talking like that, Yumi can no longer hold back her frustration and ends up with Tamura... On the way home that day, Yumi makes a suggestion to Yumi, saying, ``How about stimulating your husband?'' That evening, Yumi confides the idea to her husband...