In the summer of 1981 when I was 16, I stayed with my dad, his 2nd wife and my 12yo step-sister, Sarah, for two weeks. Since my dad and step-mom worked, they asked me to keep an eye on Sarah. That wasn't hard at all since she had changed a LOT since the last time I saw her six months before. Even though she was 12, she had already started to develop a very nice body. Her mom had a terrific build with huge boobs so I wasn't surprised that Sarah had started along that same road early. She also had the cutest smile that showed off her new braces.
I had known Sarah since she was 7 and we got along pretty good. We'd watch movies and swim in the pool most of the time. Watching her run around in a wet bikini was driving me crazy though. A few times she'd climb out on the ladder and the bikini bottoms would slide down giving me a nice look at the top half of her cute little ass before she'd quickly pull it back up. I had to put a towel over my lap a few times to hide a developing hard-on. It didn't help that her white swimsuit was made of thin material and slightly see through. I could see her nipples and even her patch of dark pubes. She'd walk over to me to talk after climbing out and it was so difficult not staring right at her transparent bikini.
Then one day something amazing happened. She did a high bounce dive off the board and when she hit the water her bikini top popped off. She came to the surface all embarrassed with her arms around her boobs telling me not to look. I was so tempted but I turned around the other way. I heard her swim to her floating top and then she started getting upset saying her top was broken. I asked what had happened and she said one of the straps had snapped right off and she couldn't wear it. GREAT! I thought. I told her to just go inside and get another one. She said this was her only one because she had outgrown her other swimsuits. Then she said her mom always got home too late every day to take her to the department store for a new one which meant she couldn't swim again until the weekend. Jokingly, I said it's too bad you can't just skinny dip, and then I chuckled.
She was quiet a moment then asked if I was serious. I paused and then asked what she meant. She asked if I really meant she could skinny dip. I just shrugged and said it was her pool; she could do what she wants. And all of a sudden my heart was beating very fast thinking of her stark naked in the pool. She was quiet again and then she said she peeked outside one night a couple of weeks before and had seen her mom and my dad swimming naked. She had watched them for 30 minutes swimming and walking around naked and thought that it looked like fun. Now my heart was beating so hard my legs were shaking. And then she asked if I would skinny dip, too. I almost passed out. She said she'd feel weird if it was just she, but if I did it too, she'd be able to do it.
Once I managed to control my suddenly heavy breathing, I said sure, I could do it too. I did sound like fun. Then she told me to go first. I said sure, but could I turn around first? She said okay so I did. She was pressed up against the side of the pool so I couldn't see her body, and her broken bikini top was lying on the ground. I asked if she really wanted me to swim, too, and she just nodded. I said okay. I reached for my swimsuit, my heart racing even faster than ever. In just a moment I was about to be naked in front of my 12yo stepsister.
And then I paused as a thought occurred to me. Sarah had a knack for playing practical jokes. I suddenly wondered if she was doing this just to get me to drop my pants, and then laugh and back out of it. To be honest, that didn't really bother me because I'd be more than happy to show off my body to her, but I really wanted to see her naked, too. And I mean REALLY wanted to see her naked. She asked why I was taking so long and I looked at her. Damn she looked so cute....and hot! I told her I thought she might be playing a joke on me just to get me naked and then not do it, too. She looked at me innocently and promised she wasn't.
Then I told her that she had to pull off her bikini bottoms first and toss them on the side of the pool. She hesitated and said that she wanted me to go first so that she'd have the guts to do it, too. I said that if she took her bottoms off, I still couldn't see her. Then I'd strip and she could see me first. That way, I'd know she wasn't just kidding around. She hesitated again. Then she finally said she'd do it. I almost jumped up and yelled, "YES!" She slowly bent down and removed her bikini bottoms under the water. I wanted so bad to leap in and get a good look at that tight little body of her's, but didn't. I was hoping that I'd soon be able to anyway.
She lifted her wet little bikini bottoms out of the water, tossed them on the ground and said "There. Now it's your turn." I looked at the bottoms and wondered if she'd get upset if I put them in my mouth and chewed on them. Probably. I looked at her and knew that the time had come. I asked if she had ever seen a guy naked before. She smiled shyly and said that Rick Newly had showed her his thing when they were eight, but no one else. I smiled and said "Well, you're about to, so get ready". Her eyes were glue t me as I suddenly shoved down my swimsuit and kicked it off. I stood there stark naked as she stared at me. Her eyes were wide open. Not just because I was naked, but because I had a full blown boner. All the excitement and anticipation had gotten me so worked up my dick was at full mast.
"You have an erection?" she asked, amazed. I said yes because being naked made me excited. She stared at it some more and I made it bounce by flexing my ground muscles. She squealed at that. Then I said it was her turn to show me. I wanted her to swim to the shallow end and walk out of the pool so I could get a full look at her. Her face turned bright red and I thought for a moment that she actually would back out. But to my absolute delight, she said all right. She swam along the side to the stairs in the shallow edge and stopped. She asked if I was ready, and I said she had no idea how ready I was.
And then she stood up and slowly walked out of the pool.