"Crystal, I'm going to cum," I managed to say. That caused her to increase her bucking on top of me and raised the volume of her moans until I shot my...load in her. A second later she let out a long sustained whimper as she finished. Crystal crawled off of me and laid next to me where we shared gentle kisses as our breathing and heart rates returned to normal. "I suppose you have questions?" she asked after awhile. "A few." "Okay, let me see if I can help. First off we are going to be alone. You reach around to lather her fine tits, then take time to massage the slick flesh. She leans back to kiss your chin, then makes a surprised noise as your cock, now hard again, presses on her butt. You slide the bar down to her pubic mound, make round motions to build a lather, then rub her clean with two fingers. She reaches back to squeeze your cock, and you nip at her ear. She grins. Her eyes remain closed as she leans back against you, enjoying the hot water pouring down her front. You. "There's only one bed..." But maybe the couch folds out," I said beginning to get the picture. Chelle shook her head. "Oh, like us." She nodded. I finally got it.Tuesday, I walked with Trish after class. "Thanks for Saturday. That was a lot of fun. Chelle and I don't have a lot of friends. Most wouldn't understand."Trish looked at me, puzzled."What it's like to be a twin and love your other half..." I said and waited.Trish thought for a second, looked into my eyes and she knew, that I knew. She. Waking up this morning, I felt defeated and guilty; not a very good combination for a man to feel. For the last four nights I had used my wife to relieve my sexual tension caused by her little sister, only it wasn't working. I had a feeling nothing would work until I was balls deep inside Beth’s sweet young pussy. I took my head out of my hands and walked to the sliding glass door. Sara and Beth were both lying on their stomachs sunning themselves. Beth had pulled her bottoms up into the crack.