If I remember right it was the last day of eighth grade and I decided to go and hang out with my friend who we will call D. I always flirted around because I was curious and wanted to experiment at the time. So I would always talk about masterbation with him or try to do something with him without making it really obvious.
So on this day we snuck over to his neighbors/friends yard next door and jumped in his pool. After swimming for a while I started joking around and then one thing led to another I got naked and started swimming. This was all happening while the neighbor was inside but he wasn't watching. My friend X wasn't skinny dipping but he was joking around and watching.
So I began to get really horny so I decided why not, and started masterbating as a 'joke' in front of him. I remember he just stood there in the water and watched me as I masterbated. After a while I began to have an orgasm and when it hit I kinda clinched or moved weird which caused my friend to ask, 'did you cum?' I tried to play it off but he knew I did. I love to look back at this cuz that was the first time I skinny-dipped and masterbated in front of a friend watching. It wasn't the last time though. I know he must have enjoyed it because he just stood and stared silently. To this day I wish it had gone a bit further with me and him! Oh well at least I have this memory.