A couple of years ago my friends' mom and dad had an above-ground pool installed and we spent a lot of time in it. A few days ago I went over and knocked on the door, but there was no answer. I walked around the back and he was in the pool, resting against the edge with his eyes closed. I wanted to scare him so I snuck up and splashed water in his face, and it startled him, but then he laughed and told me to get in. I told him I didn't have anything to change into, but he said don't worry because he didn't either. It took me a couple seconds to realize he was swimming naked. We had seen each other naked before and it wasn't a big deal, so I stripped down and jumped in. I had never been skinny-dipping before, and I loved it because it was so freeing.
We swam around for a while, and I started to get a little hard a few times because of where I was, but the cool water shrunk it back down. Eventually we got thirsty so I put a towel on and went to get us a couple drinks, and when I went back out he was laying on a raft getting some sun, and didn't mind that his penis was displayed like nothing. I handed him a soda and sat on the edge, just as open with my legs spread apart dangling in the water. We stayed there and talked and, again because of where I was, I started getting hard again, but this time it didn't go away. I tried to hide it, but he saw it and laughed. He made a couple jokes about getting horny in front of him but then said it was cool and that it happens. This made me a little more comfortable, so I sat there proudly displaying my hard on. He then asked me if I ever jacked off outside, which I hadn't, and then started telling me how great it was and that he did it all the time. he kept talking about it, and then he started getting a hard-on of his own, letting it stick straight up. He laughed and said we shouldn't waste them, got a handful of water and started stroking himself. My heart was pounding, but I started masturbating watching him, and he was right that it did feel great doing it outside.
He came first, and when he did a huge arc of cum shot out all over him before flowing out on his hand. He kept playing with himself until it went soft, then kicked his way to the edge, scooped up most of his cum and flung it into the grass. He continued to lay there while I kept stroking, and when I needed to cum I climbed down the ladder, squatted and let it fly out into the yard. I must have shot out five huge squirts of cum before it finally stopped, and after I squeezed the rest out I got back in the pool to cool off. After a few minutes he started laughing, and when I asked why he said the cum made his dick stick to him. He slowly peeled it off, then rolled off his raft to wash the rest off of him.
Eventually we went back inside but stayed naked, even walking past his younger brother in the living room. He said we were weird, and my friend just said his brother was jealous, shook his penis at him and we went upstairs. Nothing else happened, but we just laid around naked for the rest of the afternoon, even after his mom got home. I was embarrassed that she saw me naked, but surprisingly she didn't mind it. I guess he walked around naked more than I thought.
I haven't been swimming over there since, but I'm not planning on taking any trunks with me for the next time.