I am single male in my mid-fifties. During the past few years, I have been wearing skimpier and skimpier swimsuits at the beach (except for nude beaches where I wear nothing), I have been masturbating more, and I have been exploring and enjoying sex with my girlfriend more than ever before. I have worn Speedos since I learned how to swim and was always uncomfortable with boxer-type swimwear.
About fifteen years ago, I purchased some spandex bike shorts and tights that I use for working out. At first I wore regular jock-straps underneath, but eventually went to thongs to hide the strap lines. I found the thong underwear very comfortable and then began to regularly wear cotton thongs as underwear. About four years ago, I was on the beach with my girlfriend, who is in great shape, and saw a young woman wearing a thong bottom. I jokingly asked my girlfriend if she would consider wearing a thong. I did not get an answer, but she pondered it a bit.
The next week when I went to her apartment to pick her up to go to the beach, she answered the door wearing a yellow two piece suit with a thong bottom. My eyes popped out of their sockets as she showed it off to me. She then said that she has a little gift for me; it was a thong. I took off my clothes in her living room, and put on the new thong. It felt great and I became erect in no time. She, of course, had to feel it and likewise, I felt her thong; it took us a while before we left to go to the beach.
Since that time, I have regularly worn thongs at the beach; occasionally, we go to a nude beach but otherwise, we wear our thongs. I do a fair amount of traveling; during the warmer weather, I always try to go to the beach for a few hours to break up my driving. As I said before, I have been wearing skimpier and skimpier suits, and this past summer, I purchased some g-string, including one that had a sliding pouch in the front. On one of my trips, I went to Assateague Island to lay out on the sand. It is not an official nude beach but at one time, there was a good sized nude crowd that hung out about a mile away from the bath house. Now, they have been replaced by thong and g-string wearers.
This day, I put on my zebra patterned sliding g-string covered by shorts and a tee shirt and walked north from the bath house. After about a half-mile, I noticed other thong and g-string wearers near the water line. I took off my shorts and tee shirt, walked another half-mile, put down my beach towel, and set up for a few hours of reading and sunning on the beach. I slid the pouch so that it only covered the bare essentials.
I was lying on my stomach when three women who were about forty years old passed by. They were all wearing bikinis and having a great time walking and laughing. When they passed me, one of them said 'nice ass'; I turned and shouted 'thank-you' as they continued on their way up the beach. On their way back, I was now sitting facing the water, the same woman shouted 'nice suit.' At that point, I got up and the four of us started talking for a while. One said that she wished her husband would wear a g-string; the other two were divorced. I had a camera with me and suggested that we take some pictures. The married woman took the pictures. The first picture was taken from the front, then from the rear. One woman says to the other, let's put hands on checks; so they did and I put my hands on their bottoms. I then suggested that they take off their tops. I got a nice slap on my face, but then I said that they had their fun, now let me have mine. After some bantering, they unreluctantly took off their tops and a picture was taken with me holding their bras in my hands with my arms around their shoulders. They wanted one more frontal picture with their hands on my pouch. By this time, the g-string had a very large bulge in it; their hands were rubbing my swimsuit nice and slow. My camera ran out of film and we went back to talking a bit more. The picture taker, the married woman, said she liked my suit and proceeded to feel it. After about three strokes, her finger got caught in the top of the g-string pouch and my fully erect cock was exposed to the air. She laughingly said that she was sorry. I asked if any of them wanted to explore the dunes, but they said maybe next time. After thanking them for taking the pictures, they went walking back to the main section of the beach.
Meanwhile, my cock was pumping away. I ran to the dunes, took off my g-string, shot my load, went for a swim, and enjoyed the rest of the afternoon by myself. I look at these pictures from time to time; they help me get erect. I have not told my girlfriend of this experience. We keep on going to the beach, and have matching thongs and g-strings; she often goes topless. We both like to masturbate and play with each other, and we continue to have glorious sex.