The Invited Man(2017)

Original title: 초대남

Min-ho wants passionate sex and his wife Eun-kyeong says sex is just a verification of love. Min-ho wants unique sex again tonight but Eun-kyeong only wants the usual sex in bed. One day, Eun-kyeong gets sex toys at work. She doesn't like them at first but she can't get over the great feeling from the massage shop and starts touching herself. Min-ho sees this and he gets horny. In the end, they have sex that they will never forget.