Returning home for my wife's childbirth, her sisters were all dressed provocatively, showing cleavage and panties, making me fully erect. Since my wife's pregnancy, we've been sexless, and I was painfully hard. Of course, they noticed and, while my wife wasn't looking, one of them offered to relieve me. "You must be horny," she said, and I couldn't resist their kindness. I kept telling myself this wasn't cheating, but honestly, I just enjoyed the young ones.