Search Results: taking long to finish

I have been having an affair with my wife's sweet beautiful younger sister after she moved in with us after their parents divorced. It started after during my wife's second pregnancy when she was bad with morning sickness all the time and her sister took care of her as well as the household choirs while I was at work. It started up after she caught me "taking care" of myself" in the basement and she laughed and giggled encouraging me to finish up as she wanted to watch, then she deceided to" help "me herself. After she offered to take care of my needs while my wife was unable like she did with everything else and thats where the affair started and though I was madly in love with my wife I fell big time for her younger sister.
Eventually my wife found out and there was hell to pay for it and she took the kids away from a month but came back after her sister had a discussion with her. So they both met me in the living room where they told me that they both love me and the younger sister my mistress was pregnant with my child and that they both want to live together as both my wives. So my head still can't get around it and they share me equally in bed on different nights.
Life is pretty sweet right now but I wonder about the future and if this can last long term as I love them both. So can a marriage with three people work?