This is not a real MF story, but more of the idea/fantasy of one.
When I was 15, I was the team manager for my high school's indoor track team that year, and at practice one day, I was in the field house office getting uniforms out of boxes to be handed out later, and putting attendance on the computer. An injured runner, Katie, helped me out, teaching me a couple of things since this was my first year doing this. Well, she's pretty hot. About 5' 4' or so, nice body, brownish hair pulled back. She also had a twin sister.
Well, as she bent over a couple of times, I noticed she was wearing a pink thong. I hadn't jacked off in a day or two because I was so busy, so this gave me a hard-on within seconds. I had to hide it from her by scooting closer to the desk!
When I got home, I went right up to my room and jacked off to the image of her in nothing but that thong. It was one of the best sessions I've ever had!
Thank you Katie!