I would like to share this experience I had some time ago which I recall many times with great clarity. When I was in my early 20's, I lived for a while on mobile home site and my small end bedroom was overlooked by a another on a slightly higher elevation. This caravan was occupied by a married couple that had recently moved in. I was alone one morning as my parents had left for work and I happened to notice the woman looking out of her window. Standing up, I could not see her but but using the reflection of a small mirror I could see that she was looking with some interest at my window as I was only wearing my pyjama bottoms. I felt aroused at the thought of her wanting to watch so with the mirror set, I started with storing my bedding on a shelf above the window. Then when I knew I had her full attention I fumbled with my pyjama cords. I could not help but have a full erection and I could see her looking with a half smile of anticipation on her face. I can remember the thrill of finally dropping my pyjamas while watching her look. I moved out of view and wondered what I could do so it appeared natural to remain undressed. I took a sewing measuring tape and then moved back in view and pretended to measure my cock and record the measurements in a notebook (that raised a few smiles). I also took the opportunity to play with myself so that she could have a good look. I was so aroused that it was only a matter of time before I went past the threshold and could not hold back a fearsome orgasm. I watched her as I came and saw her expression turn to disbelief (disgust?) as I was reaching my climax. I am not sure that she saw the actual evidence of my orgasm through the reflection of the glass window but I knew that my body mmovements left no doubt to what had happened and especially as she saw my cock shrink back to its flacid state. Afterwards, I felt very guilty at what I had done and was worried about her husband coming over and complaining. I kept away from the window and avoided the chance of meeting up with them. However, the inevitable happened and as I was coming back from shopping she was outside and asked me to help move a gas container. She appeared normally friendly, asked my name and so on and thanked me for my assistance. The only reference she made that might have had a double meaning was a remark that it was nice to have a strong man around. So a couple of days later, when I was on my own again I moved around in my pyjama bottoms and once again saw her looking out of her window. Our relationship of voyeur and exhibitionist continued throughout the summer and looking back now I am sure that each enjoyed the experience. Once I knew that I was not upsetting her I was able to be more exhibitionistic and orgasm freely. What I thought was a look of disgust was actually one of extreme anticipation which she always had as she watched me approaching my orgasm. When we met passing by, sometimes with her husband, we use to smile and say hello and that was that. There was never any look of recognition or inference to the fact. When my parents found a house I had to move in advance and never had the opportunity to say goodbye. However, the memory of that summer remains in the upmost of my mind and at times, usually in the early hours of the morning, I can recall the times in vivid detail. In fact, as I close my eys, I can see her reflection now and she has that half smile of interest.