I have a twin brother and we have been doing things with each other since we were little. Our mom caught us kinda grinding on each other, naked when we were 9. she made a big deal out of it and took us to a shrink. The shrink told her we were just curious and would out grow it.
We did until we were 15. We had separate rooms and when I would get scared I would always go and sleep with him. I remember once a girl at school had a crush on him and I was furious. He asked me what was wrong and I told him I didn't like the idea of another girl kissing him and holding his hands.He has always been a smart ass and he said you want me to kiss you. My brother to me was the best looking boy I had ever seen he was what you would call back then a headbanger I guess I was too and we both have jet black hair and green eyes. I told him yeah I guess I did want him to kiss me. Him being him said he would if I took off my shirt first. I was well developed for my age and removed my tank top. He just sat there looking at me and pulled my hair out of my ponytail. He leaned over and gave me a quick kiss on the lips. I sat there silent and I grabbed his hand and put it on top of my bra. He started kissing my neck and my breast and said OMG your going to tell. I said no way. So he then pushed my bra up so he could see my breast. He told me I was the most beautiful girl he had ever seen and if I wasn't his sister he would fuck the shit out of me. I said maybe that's what i want you to do. We were home alone except for our older sister and she was in her room as usual.
I reached down and felt he had a hard on. Neither of us had ever had sex before and was fumbling along. We both ended up naked. He had me lay down and while he was kissing me slid his dick inside me. I remember shuttering and biting his shoulder so my sister wouldn't hear. He was moaning and kissing my face and said he had thought about me for along time. It was over really quick.
But that was just the beginning. We have continued to have sex and i guess a relationship since that very day. What happened all those years ago defined who we are today. Neither of us are married. We have dated other people but nothing seems to be as complete as it is with my twin. We now share an apartment and sleep in the same bed. We look to much alike to pass off as husband and wife. I love my brother with my soul but sometimes I miss the fact I won't ever be able to have a child with him.