At the beach she picked out an empty spot. I offered to oil her up and she lay on her belly while I did her back and legs. After a while we went swimm...ing. The water cooled us off then the sun warmed us. As we were warming up -- and making out a little -,the Couple and the Big Black Guy (BBG) (as I called them in my mind) walked by, saw us and set up about 10 yards away. We returned their greetings and watched them, laying on our bellies. The husband removed his clothes, then his Wife's towel,. As the train moved off I became aware of a man behind me, I could feel his cock against my buttocks. In the crush and the sway of the train, his cock slid across my buttocks and in between the cheeks of my bottom. Immediately my nipples hardened in reaction to a strangers cock in between my bum cheeks, I realised it was getting harder and bigger and my nipples became visible to the man and woman facing me through my thin dress. They looked at each other and then to me with a knowing smile on. I was squirming and groaning and god knows what else beneath her attentions. This woman was a seasoned pro. She had switched to one hand on my cock, but started taking it deeper and deeper into her mouth. I felt a kind of clustered resistance at the back of her mouth. I didn’t quite understand, but it felt good scr****g around my cock, so I thrust upwards. Anne’s eyes bulged slightly as my cockhead slid down her throat an inch or so, but she kept her rhythm and started to do it herself.. We ate and all made small talk as we normally do and i felt a bit more comfortable,then Ray commented that it was snowing outside and she wandered if i would give her a lift to town as she was going out with her freinds.No problem i said "Ill just help your mother clear the table while you get ready,take your time"."Glad to see you both getting along so well adam," May commented as i put away the plates and cutlery.I felt my heart beat a little faster,is this a trick?Has ray said.