Billy had come to stay a few weeks with us. That first morning, I forgot about him being with us.
At the time, I was 15. It was summer and I was out of school. Mom had remarried during the winter and we moved into my new step dad's house. He had a son from a previous marriage. His name was Billy. He was 17 at the time.
Billy came to stay with us for a few weeks so he could be with his dad. His room was next to mine. That first morning, I got up and headed to the bathroom. I went my usual way which was through Billy's room. I had forgot that Billy was with us and I opened the door and walked right in. That's when I was shocked. Billy was laying in his bed with his hard dick sticking out the opening in his boxer shorts and he had his hand around it. I stood there looking at it with my mouth wide open. I said 'I'm sorry' and turned around to leave. As I did, Billy said 'You might as well stay and watch. You've already seen me'. I actually did want to stay and watch. It was my first real live dick I'd ever seen. I stopped and turned my head to look at him. Billy said 'Maybe you can help, if you want to'. He then took his hand off his dick so I could really see it. I turned around and Billy patted the bed motioning me to come sit by him. I slowly walked over and sat on his bed. Billy said 'Go ahead and touch it'. I reached over and put my hand on his dick. It felt so hard but was very smooth feeling too. Billy said 'Put your hand around it'. I did and I then started moving my hand up and down on it. Billy let out a 'Aaahhh; that feels so good'. I continued to stroke it. I was wearing a short little nighty and Billy looked at my bare legs and reached over and started touching one of them. He said 'You feel so good'. Then he said 'Go a little faster and you can see me cum'.
I went faster while Billy ran his hand over my leg. All the while Billy was looking at my legs. He then said 'Aahhh, I'm about to cum. Aaahhh'. He then stiffened up and squeezed his hand on my leg as his body shuddered and with a grunting sound, stuff started shooting out of his dick. It went up in the air and landed on his stomach and some of it got on my arm. I knew about this but was surprised at the amount of cum he shot.
During his stay, we did this quite often when our parents were at work. Billy wanted to do more things but I wouldn't let him. I did let him finger me and get me off. After this, when I started going out with boys, I'd always give them hand jobs. I knew they'd enjoy it. I'd also let them feel me where they wanted to while I did it to them. Tits, legs and also my pussy. I'd always take along a purse when we went out and I kept my purse full of tissue just for this. I have always felt a special power in the fact that I can get boys so aroused and can make them cum so easily.