...Then when they got about 3 meters away they turned back towards the beach and just floated there. Now I had the perfect view of their sexy asses on...top of the lilo and at my face height. They both had thong style bikini bottoms on and I could see their pussies and assholes against the tight material. That was it, my hands automatically undid my swimming shorts and my hard cock sprung out. There was plenty of other people in the sea but no one could see me wanking furiously beneath the water.. "Let's have some quick fun before we eat. I so want at you, Lisa." Oh, Chelsea, control yourself," responded Lisa, "we don't want to embarrass our friend here, do we?" Of course we do, or perhaps instead he will like it and join in." And with that Chelsea pushed Lisa down and straddled her stomach. I sat intrigued as I watched her pin Lisa's arms above her and then lowered her face close, whispering, "You would like that, wouldn't you, girl?"Chelsea kissed her full on the lips then, with Lisa. Her fingers gently but firmly rubbed and stroked there and it felt better then anything I had ever managed to do. Im not sure how long it had been when I heard myself moaning softly and felt my back arching and my toes curling. I felt my heart pounding and my breathing heavy. But she seemed to know my body better then I did. I am not sure if there are words that can explain the feeling but the little special place there felt so good and even though it is very small and tiny if rubbed just. I made no attempt to conceal the small tent that my cock was making in the sleeping bag and I finally responded,"I'm sorry Mom. For a couple of minutes there I forgot that you were my mother and I just saw you as a highly desirable sexy woman. I hope that I haven't offended you and that you can forgive me." I managed to look stricken as I came out with this and Mom's re-action was almost predictable.She turned onto her side to face me and whispered, "What's to forgive? You certainly haven't.