I enjoy this site very much...
This story happened to me just about two years ago.
I was staying in my sister's house to tend to their son, Ron, my nephew. Ron was then 11 years old and I was 18. My sister and my brother-in-law worked abroad. They have a very luxurious house, complete with swimming pool and a mini gym.
I was a gymnast when I was in my grade school, a volleyball varsity of my school when I was in junior high, and basically sporty and athletic. I love the mini gym a lot.
And Ron loved to be around when I am in the gym or even in the swimming pool. And I would be amazed to notice his bulge beneath his shorts or trunks. At first, I thought it would just be normal. And his being around me had been a tradition and had been our routine since he was very young. But what was disturbing when he was already 11 was that he would position himself in a way that he would be at my feet. And he would all be an eye on me when I do my crunches (scissors, etc.). And when I would be doing my lotus seat or 180-degree leg push or split or the seat angle pose with groin stretch or the upward bow pose, I would catch him several times looking at my crotch.
When I go to the gym at the house, I would always be in my shorts, in tiny and light shorts because they allow easy movement. For as long it is tiny, the shorts could either be tight or loose. My tight shorts would be light pink, beige, or white lycra or stretchable latex shorts. My loose shorts would be white, beige or light gray cotton sweat shorts. Then I would wear a sports bra. And when I go to the gym at the house, as much as possible I would avoid wearing my panties so that I won't be fixing my panties every now and then after I have done leg stretching, squatting, Indian sitting, and the like, where often the panties would inadvertently get inserted between the butt cheeks, and worse, at the slit, and sometimes the panties would move from one side of the labia, and all these give a lot of discomfort of fixing it every now and then while you do the exercises.
Since then, I got conscious about my attire in the gym. I observed myself and constantly looked at the mirror, especially to my bottoms to see whether I was making anything distasteful on the sight of my nephew. And I was shocked that when I do my crunches, my mound was very noticeable; and there's a very nice camel toe in it, especially when I was in my lycra shorts. There was nothing distasteful with it, the way I saw it, even when I do my legs stretching and 180 leg split. It was just that the nice bulge and the mound were very much apparent.
It was different when I use my loose cotton shorts. While there were no panties to move from one side to another that I sense to be very uncomfortable, what I saw in the mirror when I did my leg split or the rock the cradle pose was my labia on one side of the shorts - not quite exposed though, but still could be seen. And I was certain then that this was the reason why my nephew enjoyed his staying in front of me and to my feet when I do my exercises.
Since then, I knew that my nephew had been masturbating to the sight I was accidentally been giving him. The succeeding encounters, I deliberately show him what he has been after; after all, I thought he could never take it. And I knew, I was doing it very discreetly and with a bit of decency.
And doing this daring act to my nephew was a bit naughty yet with a lot of struggle on my part. On the whole, I enjoyed it. There would be times that Ron would excuse himself out; and I could just anticipate where he would be going and what he would be doing.
But the fact remains that in many instances, I was aroused with the thought that my nephew was masturbating with the thought of me. And I would imagine him masturbating and squirting his load. Such image would be my fantasy when I would do my own a bit afterwards.