I had this happen several times over the years. One guy in Philly used to do it with his wife and son at home. He would always say just keep it quiet and he was always the one who would initiate the fun with his big Dick. I always felt really awkward. He then moved to a studio and still screwed around there. And then he and his wife moved to a new house and he continued. I guess I found it hot because I kept returning. On another occasion, also in Philly, a guy hopped on top of me and rode me while his boyfriend was downstairs. Afterwards, the three of us chatted in the kitchen and clearly the bf knew what went on. I’ve had a roommate of bf join the massage before too.