With the wife sunbathing with her sister I had gone for a walk in the dunes hoping to find some action of the bi variety. I climbed to the top of the nearest dune to the camel park and found what I was looking for, a guy on his knees just waiting for a passing cock. I stripped off and soon we were enjoying each others dicks. After a while he got out a condom and lube and offered me his arse,I needed no urging and was soon pounding away. This is where it got interesting! I happened to glance around and saw a couple watching us behind a bush. They were both around their 60s and fully clothed. I had no intention of stopping and thought that the sight of two naked men fucking would send them away.... I was so wrong. The woman started to walk around the bush until she was in full veiw of us and was watching with a smile on her face. The guy joined her and started to fondle her tits. the lady took her sun dress off and stood there as naked as us. I watched as the man knelt and licked at her pussy, all the time still fucking the guy I had met. Eventually I could not hold back and shot my load. I pulled out and looked at our watchers, she smiled ,he smiled and they went. I thanked my bottom and also left the dunes. I wonder if the couple have as fond memories of us as i do of them.