We had known Riley and Rachel, the twin girls next door, for about eight years, ever since their parents bought the home next to ours. Their dad, Gary, and I were golf buddies. He and his wife Becky, along with the girls, were frequent guests at our place for BBQ and swimming in our pool.
Gary and Becky moving in next to us had worked out great. My wife and I were nudists, and also marginally into the swinging lifestyle. By happy coincidence, it turned out that they also were practicing nudists and occasional swingers. Over the past several years, we had "partied" together on numerous occasions.
Becky was gorgeous. Short (5'1"), slender, firm little 32B breasts, and insatiable in bed, she liked something my wife Donna didn't care for: it was ok for me to cum in her mouth. Donna, who at 5'11" and 295 pounds has a BBW type build, enjoyed Gary's big cock, something I didn't have to offer. Gary's massive rod is almost 8 inches long and very fat. I'm much more average. And Gary seemed to enjoy having occasional sex with a woman who outweighed his wife by over 100 pounds.
Our wives were complete opposites, body style wise, and I guess Gary and I both appreciated the contrast. While neither of the ladies was truly bisexual, they seemed to enjoy putting on a little show for us guys once in a while, and each had tongue-lapped the other to orgasm on more than one occasion.
And while Gary and I were decidedly heterosexual, we had experimented a little with oral sex on each other, at the urging of the ladies, and neither of us was shy about licking a pussy that the other had just deposited a sperm-load into.
In fact, we had gotten to the point that Gary and Becky were the only couple that we engaged in swinging with, and likewise, we were the only couple for them. We enjoyed each other as much for the friendship and social nudity as the occasional sex, and had by mutual decision installed a gate between our private backyards to make visiting easy without having to get dressed to walk between our homes.
Donna and I were a little older than Gary and Becky, but that had never been an issue. I recently took an early retirement from my job at the age of fifty and have been enjoying a life of leisure. Not luxury, mind you, but leisure...we have a nice home that's paid for with all the room and amenities we need, including a pool.
The twins had been ten when the family moved in next door. Now they had just recently turned 18, and it was obvious they were both going to be as good looking as their mother. Just over five feet tall, both had developed nice curves and pert little apple-sized breasts with dark pencil eraser-sized nipples and areolas. Like their mother, who was part American Indian, they both had high cheekbones, dark complexions and very scant body hair with just a light dusting of black pubic hair. Riley wore her dark hair very short in a pixie cut, while Rachel was letting hers grow long and often had it in braids. Both of them had taken to me early on, and now they both called me "Uncle" Bill.
My wife and Becky were having a "girl's day out" of shopping and lunch. I was messing around on the computer one summer morning when the phone rang. I answered, and it was Riley.
"Hi, Uncle Bill, it's Riley. Is it ok if Rachel and I come over to sunbathe and swim?"
I knew that Gary was at work. I wasn't doing anything important or planning to go anywhere.
"Sure," I told her. "Come on over. Let yourselves in through the side gate. There's sodas and bottled water in the fridge in the cabana."
"Thanks, Uncle Bill," Riley said. "We'll be right over."
I had spent a lot of time and money on the pool area. It was a very private, lush tropical setting with lots of plants, a cabana with changing area and restroom, and an outdoor open-air shower. I often went outside to shower when the weather was nice. My wife and I never wore swimsuits when we used the pool, and Gary and Becky and the girls had joined us for skinny-dipping on many occasions. I still remember the first time the girls, who had grown up visiting nudist resorts with their parents, found out that it was ok to swim "nekkie" at our house. They both swam like little fish, and had dark all-over tans in the summertime every year. Of course, when the girls were around we always made sure there wasn't any overt sexual activity going on.
Bottom line, I was used to seeing the kids "nekkie", and they were just as accustomed to seeing me nude. I guess I just hadn't been paying attention to how fast they were growing up, because when I looked out the window into the pool area about thirty minutes later, suddenly I didn't see two kids, but two very attractive young women.
Both of them were slathered in suntan oil, their sleek, nude brown bodies gleaming in the sun. Rachel was lying on her back, one leg propped up and reading a magazine. Riley was face down on a chaise lounge with her feet towards my vantage point in the kitchen window. Her legs were slightly spread, giving me an enticing view of her firm little ass and tender young pussy.
It took a second or two before I realized that she had her hand tucked up under her and she was slowly masturbating. Her hips were very gently undulating as her finger caressed her labia and clit. I was captivated. My mouth went dry and I felt my cock start to thicken.
