I was thirteen and visiting my grandparents in Indiana. I had been jacking off since I was very young and was just beginning puberty. I had a small amount of pubic hair and was able to cum a little. Most of my school friends were maturing earlier than me and I was always embarrassed and avoided the after sports showers. One day while visiting my grandparents I walked out to the highway to check the mail when a car stopped with a middle age, pudgy man driving. It was a brand new car and at that age I was totally interested in cars and dreamed of reaching 18 and owning my own. He got out of the car to stretch and asked me how far it was to Indianapolis. He saw my interest in the car and started to tell me about the engine and how fast it would go. He asked if I would like to get in and see the interior.
That was back in the 1940s and kids didn't know about pedophiles, homosexuality and those kind of things. I didn't hesitate and got right in. He got in the driver's seat and started pointing out things on the dash. I was totally engrossed in looking at everything on the dashboard but noticed he started to laugh and squeeze my thigh a lot but I didn't think much about it until he put his hand on my crotch and started rubbing my dick. If I had known what kids know today I would have been scared but I was more embarrassed than anything else. Then he started to unbutton my pants and to take my dick out which for reasons unknown to me became hard the minute he touched it. I said that I thought I heard my grandmother call me but by then he had it out of my pants and was beginning to stroke it. Then I was really embarrassed and could not figure out why he was doing that to me. I was further embarrassed because I felt almost immediately that I was going to cum and I didn't want him to see. I was trying to hold back but he was probably very experienced and knew I was trying not to cum and said 'Just go ahead and let it cum'. With that I just gave up and went ahead and came. I was very surprised that when I came it was more than I usually pumped out in my solo masturbation sessions. I guess it was because he stroked it faster and didn't stop when I start to cum.
He had a rag, wiped off my dick, I got out and he burned rubber as he started down the highway and left me standing beside the road still amazed at what had just happened. While it seemed to me at the time that the whole episode lasted a long time because when he was jacking me off it was like slow motion I realized later the whole event probably didn't last over 10 minutes. Later in my teens I did engage in mutual masturbation with some of my friends but that old man on the highway in broad daylight was my very first experience.