Well, let me switch to my throwaway real quick here.
My dad dated the same woman from the time I was 4 until I was 12. After they broke up, he met a new woman who had a daughter that was a year younger than me. I saw the daughter once every two weeks.
It started innocently, games of truth or dare, randomly seeing each other in less clothes than was appropriate, swimming at the pool.
As time progressed we became closer and closer, in a very non sibling way.
We'd watch each other masturbate. We'd play truth or dare with a very different idea of what dares should be. She'd have sleep overs and I would get naked with her friends during strip poker. We'd fall asleep in each others arms. We'd dry hump. We'd wake each other with hands, fingers and tongues in places they really shouldn't have been. I've only cum from one blow job in my entire life, it was from her. Her hands are like fire on my body.
I'm 30 years old. This stuff all happened from 16-18. Almost every single fetish I now have is from things I experienced with her. I can't even explain my feelings for her. I don't just want her sexually, I want to wake up next to her. I want to hold her when she needs to be held.
It's taboo. She has two kids from other two other men. I only see her on holidays now. I'm married. I still want what we had. She is the one I think about when I'm inside my wife and want to finish.
She is a baker. Two days before my wedding, my wife went up to the venue early. That night, my step sister came over to make cupcakes which were to be our wedding cake. If she had arrived even 20 minutes earlier I probably wouldn't be married now. She showed up only 15 minutes before I had to leave for work.
Once while my wife was out of town, my step sister and I went out for dinner then came back to my house. She got completely naked then seductively walked towards me. I don't know what the hell I was thinking when I said no. One of my fetishes is panties, I always saw her in her panties before. She would sit on my face with her panties on and tell me to do things. If she had had panties on the night she was over, I would have done things I regret. Now I regret the things I didn't do.
Don't let your kids sleep in a tent in the backyard. We would set a tent up in the back yard every weekend we saw each other. That is where the things occurred. That is where I lost my innocence and found physical bliss.