My job relocated and i didnt go with it. My severance was 12 weeks of pay. I decided i would take the summer off and just enjoy the break from the working world. My sister inlaw who i will call Sil had been planing a trip to florida to visit family. Since i was now free, she asked if i wanted to go with her. I packed and we left the next morning. The 2 day drive was long. We got there after dinner. That night we sat around the pool talking about the new signs they had up. Its know that whsn the relatives dont have visitors they tend to be naked. They set up the pool in a tiki style and have a lot of signs up about nudity and clothing optional. I was on a blow up mattress and Sil was in yhe regular bed. We were awoked in the early AM by a hissing sound. The seal on the blowup gave out. Sil told me to climb into the bed. I hesitated but it was to late for any other plan. Breakfast was outside and it was already well into the 90s. Sil said it was time for swimming to cool off. She got up walked toward the pool and pulled her shift off. Her boobs looked amazing. Next was her shorts. I was staring at her ass as she climbed into the pool. I was in shock. I had never seen her naked before. She looked back and rralized i was stating. She said "what...i have to follow the signs." As she pointed toward the no clothing zone signs. I chuckled. The relatives were already in the pool. I got up and figued what the hell and joined them. We spent the rest of the day naked. When it came time for bed we had forgot to do anything about the mattress. Sil told me join her in thw bed. As i laid there it was impossible to not touch her naked body. When i woke up, sil was pressed against me. Her skin was so soft. Day 2 was the same as 1. Naked all day. When we went to bed, sil was slowly caressing her stomach and boobs with her fingers. She closed her eyes and started caressing her thighs. Her fingers getting closer and closer to her pussy. Her legs started to open. Her fi gers found her lips and slowly started to run in and out. I was rock hard watching this. I could resist and started to jerk myself off. Her legs twitched and she shook. Sil erupted with a moan as she arched her back. Thats all it took for me as i exploded in orgasm. Sil opened her eyes and started to laugh. She couldnt believe she did that. I climbed into the bed, this time Sil wrapped hefself up next to me. Her breasts felt so soft and amazing against me. Her legs drapped over mine. Day 3 it poured. We stayed inside. We were close that day her naked body often touching mine. That night we cuddled again. My hand held her breast as we slept. Day 4 was back to sunny ans hot. We were playimg games in the pool when the relatives came out fully dressed for thw first time all week. They were heading on some errands. After they left i grabbed Sil to toss her into the deeper water. She struggled and our genitals brushed against each other. We stopped. My dick pressed against her lips. She lowered herself down. She felt amazing. She started pumping up and down and almost instantly shutterred and screamed in orgasm. I followed exploding into the pool more cum than i ever have. It welt like it shooting for ever. The next day we left. The first thing we did in the hotel room was get naked. Again we cuddled in the same bed. Since then we have not told the wife about our nudity and certainly not the maturbation amd the sex. I have a feeling the wife knows we may have been naked togwther. We are very unihibited in front of each other. Sil will spend the night and walk around in her underwear or just a tshirt that barely covers her butt. Somwthing she never did infront of me. We are very close now. Always hugging and hanging out whenever possible. We flash each other all the time. Its almost a game.