I was almost eighteen at the time. A senior in high school. I ran track so I was in good shape. I was 6'1', 195 lbs (still am). My sister Sandy is one year younger than I am. She is 5'5' with a nice girl figure. She has c-cup breasts (I've checked her bra).
I was in my room one evening studying when she came into my room and asked if she could ask me a question. 'Sure go ahead.'' Have you been circumcised?' she asked. 'Ok Sandy what's going on.' 'You know Maggie.' 'Sure Jim's sister. 'Yeah, well she and I were reading in this book and it talked about most boys being circumcised. We decided to keep track of the little boys we babysat to see. We have been doing it for about two months now and haven't found one that isn't yet. I was just wondering about you.'
'What do you think.' I asked. 'I don't know' she said 'but when we were little and mom bathed us together I kind of remember your penis looking different than the little boys we babysit. I don't think you are.' 'Have you talked about that to Maggie?' 'No, I just thought about it now.' 'If I tell you, you have to promise not to tell anyone.' 'Promise.' 'I haven't been, I still have my foreskin.' 'I thought so.' she said. 'Can I see what it looks like?' 'No! Are you crazy?' 'I thought it was worth a try.' she said. 'If I did show you what do I get out of it?' 'I could masturbate you.' By this time my penis was needing some attention so that didn't sound to bad.
I decided to see how far this might go so I said 'I can do that myself. If you get naked and let me do you I'll get naked and let you do me. That sounds fair to me.' I could tell that was a little more than she had bargained for. She just stood there turning red. 'How about just my top' she said. 'Nope all or nothing' 'I have never had anyone touch me or even seen me naked before' 'I've seen you naked before when mom bathed us' 'That's different' she said. 'OK then no deal' Sandy got up and left my room. By that time either she did it or I did myself. I put my hand down my pants and started running my hand over my penis and ball sack. I was just about to pull my penis out and start to masturbate for real when Sandy came back. 'Let's do it' she said.
I got up and took my shirt off and told her to go ahead. She said. 'Turn around' so I turned around and took the rest of my clothes off. I looked over my shoulder and she had turned round and was just taking her panties off. She was completely naked like I was. 'Turn round on the count of three' she said.
At three I turned round and there we stood in all our glory. My glory was sticking out as hard as a rock. When I am erect my foreskin completely covers my glands. You can just see the tip of it if you look inside. I could see Sandy's eyes glued to my penis. 'You have grown some since I last saw you. I would say about five inches. You were only about an inch and a half back them.' 'You have grown a couple of things since as well' She blushed when I said that. She stepped over to me and reached for my penis. 'It looks different than a circumcised one.' I told her if she would pull my foreskin back it would look quite the same. 'Show me how you do it' I took my penis in my hand and pulled my foreskin back all the way. 'Now it looks like a circumcised one.' I pushed my foreskin back over my glands. I did this several times then she took over. It didn't take long before I was going to cum so I told her to do it faster. She had my foreskin flying over my glands and then I came all over her hand and the floor. I let her keep doing it until my penis got too sensitive and I started to go soft. Wow! What a climax.