"Hey Mr K, it's Sara. I got your number from dad. I'm home for the summer and was wondering if I could use your pool, just like the good old days?"
"Oh hi Sara. Great to hear from you. Sure, you're more than welcome to use the pool. I'm not home but the back door is unlocked. Feel free to use anything you need in the house."
"Thank you Mr K, you're the best."
I hadn't seen Sara in a year and barely in four years before that. Once she was in high school, she became a recluse and only left her house for school and emergencies it seemed. I was out running errands and wouldn't be home for a few hours so she had the pool to herself.
When I got home, I had forgotten Sara was supposed to use the pool. I went into my bedroom and heard music. I looked out and saw Sara sitting, reading a book. She looked totally different than the last time I saw her. She had turned out to be a beautiful 19yr old woman. She looked just like her mom.
As soon as I recognized her, Sara stood up facing me. She had some kind of yellow dress that was see through and she didn't have a bathing suit under it. I could see the dark of her areolas and hair between her legs. I knew I shouldn't be looking but she was stunning.
Sara then walked into the pool. As she stepped in, one of the straps of her dress fell off her shoulder and I could see her naked breasts. Maybe a small C cup and very nice. I could feel my cock stirring in my shorts.
As she got deeper into the pool, the dress became wet and even more transparent. Seeing her now had my cock fully hard now and I was rubbing myself on the outside of my shorts.
I watched as she swam but the dress was getting in her way so she quickly shed it and was totally naked. By this time, my shorts were around my ankles.
After a couple of minutes, Sara got out of the pool. I was now slowly stroking my cock with precum dripping. She sat on the edge of the pool, at the steps, opened her legs and started to touch herself. She was facing me so I had a great view of her body. My stroking increased as Sara increased her speed rubbing her pussy. Soon, Sara's head flew back and her body shook. My body also shook as I came at the same time Sara had.
After both Sara and I came, I just stood there with cum on the floor and my hand. Sara had got up and got her phone. I was still drunk from my orgasm but a notification on my phone snapped me out of my trance. My phone was in my shorts that were around my ankles.
"Hope you enjoyed the show Mr K?"
When I looked, Sara was gone.