To this day, I still regret the way I reacted and fantasize about what I could have done differently.
When I was about thirteen or so, I had a friend named Andrea who lived up the road from me in the village, I was on the outskirts of it. I had invited her over and we did normal 13-year-old stuff, played outside, watched some tv, messed around in my room.
Somehow I ended up in my walk-in closet for a few moments, probably looking for something, and when I came out she was on the corner of my bed, pants and panties pulled down to her knees laying on her back with her legs in the air.
This was the first time I had ever seen another girls pussy like that, I remember the shape, how there was very little hair, and how absolutely attractive it looked to me. I knew I liked women as well as men, I had for some time now, and had I thought about it I probably would have reacted differently. Instead I was so shocked I think I said 'Andrea! What are you doing?!' and promptly exited the room. She came out decent and I think things were a little weird after that, and I don't remember if she ever came over again, she moved away shortly after that.
Then last year I saw her again, she came in with a friend of mine who came to see me while I was working, it was pretty quiet at the time. We didn't say anything to each other, but it made me remember the incident, and damn do I ever regret not doing something, to this day I wonder if we might have become 'better friends'. I guess I'll never know, but I sort of hope that she reads this, perhaps we could make amends.