They offered to bring us along. When my wife admitted sex with total strangers wasn’t our thing, Terry smiled and just nodded. About 3 weeks later T...rry invited us over for a barbeque, and a lot of beer and wine later, we had swapped partners, while I fucked Shelly in their TV room I could hear my wife fucking Terry in the kitchen.Our first experience of another couple, progressed as 2 more couples from the neighbourhood mad friends with Terry and Shelly. Other than Shelly the other three wives. There was an air of excitement around Jean and me the rest of the day. Both of us were feeling very horny, but we chose not to do anything about it until later. We were looking forward to what dinner and later in the stateroom would bring.We got ready for diner. It was formal night. Both of us were dressed to the nines. Jean was wearing a low cut red dress with no back. GRRRR!!! I wore my tux. We looked great! Jean and I went down to get formal pictures taken then off to dinner. When we arrived. " Take as long as you like darling," she said cheerfully, "I love showing my cunt like this."I took my time rubbing the shaving foam in between her legs. Several cars went past, but too fast for them to see anything; if they had I felt sure mum wouldn't have moved. She was in her element, every swipe of the razor around her delicate labia brought a gasp of pleasure from her lips and finally, when I said I'd finished, she shook her head."You need to do between my cheeks, darling."Turning round. As I was sliding my cock on her bulging vulva, Terri had begun quickly pulling and releasing the pressure she was applying to her cunt. She was really getting off on this and so was I. I couldn't help myself and began lifting my cock off of her puss and slapping it back down hard when she would pull up on her pants. Each time her twat really bulged out it got a hard smack from my swollen cock, and each time my cock slapped down my step mother let out a little painful yelp. This went on and on.