I have changed the names but this story is true
I learned how to masturbate when I was 13. I would do it at least once a day in bed.
When I was 15 my stepdad, after trying for many years, got to see his kids for the summer. I had never met my stepbrother Mark 13 or stepsister Jenny 15 before.
I was excited and nevous Mark would sleep in my room. I had a bunk bed and a trundle so I could sleep 3 in there but had never had to share my room with anyone and was used to sleeping nude and wasn't sure if I would be comfortable sharing my room.
A week before we picked them up their mother asked if we would also take her other son-their half brother. Mom and stepdad said that we would be happy to take Ben 11. Great another person in my room would I ever get a chance to jack off?
The night we picked them up Mom and Dad where putting them to bed. Ben got the top bunk me on the trundle and Mark on the bottem bunk so that our heads were close to each other. I noticed that Marks blankets were moving ever so slightly near his midsection so when the lights went out I said 'You're jacking off aren't you?' 'Yeah what of it? I'm sure you do it too' came his reply.
The next day while mom and dad were at work and my sister Mary 17 and Jenny went to town. Mark and I were sitting around watching TV while Ben played video games. Mark found the porn channel and as we watched started touching himself through his pants. 'You want to go take care of that?' I asked pointing out the fact that I had noticed 'join me' he said pointing at my hard on I shook my head 'come on, me and Ben do it all the time' he said so after a little argument I followed him to my room.
I shut and locked the door and by the time I turned around his shirt and pants were off. I had never seen another guys penis before and seeing him hard through his tighty whitey's actuly got me harder so I stripped. As he pulled down his underwear I saw my first penis that wasn't attached to my body. He was four and a half inches was about two inches smaller than mine but bigger around that impressed me. We measured later. As I removed my boxers he started jacking off. I watched him for a minute or two then sat on my bed and started myself he sat next to me and tryed to reach over and grab mine I said 'no I'm not very comfortable.' 'Just relax' he said. I let him grab it and jack me off.
I sat there for like 15 minutes before he got the right rythmn to get me going and then I sprayed 3 ropes of cum all over both of us. As I returned the favor he put some of my cum in my hand as lube. He came in about 8 minutes and he shot like a cannon and hit the wall. We did that for about two weeks before he said he wanted to take it a step further.