I don't know if this counts, as we were masturbating each other, but Me and Bea went exploring Danish nudist beaches this summer. And being naked in the sun sometimes makes us horny. But it's risky fucking on beaches on a sunny day, even though we where behind a dune, semi-hiding. But this day she asked if I wanted to make her cum, and she could make me cum after. I'm not a hard man to ask for sex, so I got a lot of oil and started rubbing her clit and fingering her pussy and ass, and sometimes pinching her nipples. All of this makes her cum fast!
I got a bit paranoid since she were moaning a bit too loud, so I sat up on my knees where I had a bit better view while continuing giving her pleasure. Bae had her eyes closed and focused on the warmth from the sun hitting her naked, exposed body, and my fingers touching all the right spots. But suddenly I saw something in the corner of my eye and turned, and two women in their 60s and a small dog walked on a path right behind us, looking right at us. 8 meters away. Looking right at us! Me with my fingers deep in her pussy, on my knees with my stiff cock peeking out between my legs. Looking right at her oily pussy and my precum glimmering in the sun.
I pulled my hand back and lay down quickly on my stomach (and on my massive erection) and told Bae the situation as calmly as I could. She freaked out a bit, so we wispered franticly back and forth and stayed completely still for about five minutes. But after about 10 minutes and a lot of scouting in any and every direction and planning what to do if it happened again, she told me to continue. She was so close!
I eventually made her cum, then she jerked me off till I came as well. No fucking, but still sex on the beach!
Now, I don't know what the danish girls in their sixties (and their dog) saw or thought about the situation, but in Danmark where nudist beaches are pretty common I bet alot of people walk up on people having sex. So, it might not be the first nor the last time these ladies have run upon some horny nudist trying to hide while having sex on the beach!