If coming straight to this story you may want to start with the first chapter, where Tom and Lucy begin to explore each other and sex. It's called Siblings First Time.
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The next day, before our parents returned, Lucy and I talked at length. I was torn between the knowledge that what we were doing would be viewed as wrong and the teenage sexual drive that was driving me to want more.
Lucy had no such qualms. She argued that real incest meant brothers and sisters getting married and having kids, not the sort of innocent sex play that we were enjoying. In fact, she argued, we were being extremely responsible in deciding to teach each other about sex. It was much better to explore and discover these things in the safety of your own home with someone you could trust totally rather than in some dubious location or situation with someone who you hardly knew.
I didn't really buy the argument, but I was happy to accept the outcome. We agreed that we would learn all we could about sex together. Over the next few months, Lucy and I embarked upon a journey of discovery of sex techniques and of each other's body.
We had to be extremely careful, as we knew there would be big trouble if we were discovered. But we found time to be together whenever we could do so without raising suspicion. Because of when our birthdays fell, I was in the year above Lucy at school and I took to offering to help her with her studies. If our parents had known what sort of homework we were doing up in her room they might not have smiled so much each time this happened.
Lucy would lock her door, put on some music and we would spend thirty minutes or so in heated sexual activity. We had to stay at least partly clothed in these sessions, but we were able to practice our kissing and fondling techniques.
Sometimes I would lay Lucy on the bed, pull up her top and bra and spend all the time just kissing, licking and sucking on her pert breasts. Usually she would bring the session to a close by pulling her panties either off or to one side and gently massaging her clit until she came. I loved to watch how she brought herself to a climax and see the expressions on her face as the waves of her orgasm washed through her body, causing small convulsions of sheer pleasure.
Other times Lucy would kneel in front of me, unzip my fly and take my dick into her mouth. She would grasp the shaft, ease back the foreskin and run her tongue around the head. I would be fully erect in seconds and, as the pre-come started to appear from the end, she would draw the head into her mouth and suck gently. Then she would start to move her head up and down in small motions so that her lips were massaging the glans and top of the shaft. In the early days this would bring me to a climax in a couple of minutes. As she felt my cock start to jerk, ready to release its load, she would clamp her lips to form a tight seal and I would blast my hot sperm into her mouth. She would draw her mouth back slowly over the head so that she squeezed out and swept up every last drop of the sticky white liquid into her mouth. Then she would swallow, savouring it like a precious wine.
Over the months her oral technique improved enormously as she learned how I reacted to the different things she did. She also became able to take more and more of my fully erect dick into her mouth. Before too long she was taking almost the full length at times with her lips travelling down nearly to the base of my shaft. Even so, it was noticeable how I became able to last longer and longer before having to release my load.
On any occasion that our parents were out of the house, we took full advantage. As soon as they left we would dash to one of our bedrooms, pull each other's clothes off and fuck. The first couple of times we tended to only use the missionary position and it was all a little frantic and unsatisfying. Then, as we started to experiment, we began to discover the real pleasure to be had from a wide variety of positions.
It started just with me moving Lucy's legs into different positions while fucking her. We found that I could get my cock in much deeper if she lifted them up over my shoulders. Doggy style also gave me great penetration and Lucy said it made my dick press on different areas in her pussy, which increased her pleasure. We tried several positions with Lucy on top of me. She loved the control that this gave her as she moved herself up and down on my stiff cock. She learned how to increase the intensity for us both by rocking herself back and forth at the same time.
When we started to run out of ideas of our own, I got hold of a couple of porn magazines and hid them in my bedroom. We would look at the different positions used in the photographs and try them out for ourselves. We found that many of them may have been ideal for the camera, but they provided little pleasure or were really uncomfortable, but over time our knowledge, understanding and experience began to build.
There was no doubt, this was a very effective way to learn. We had the closeness and honesty with each other that would usually only be established well into a relationship. We would tell each other what felt good and what wasn't working. We would guide each other, giving direction during our love-making to get the very best out of whatever we were doing. We learned the angles of attack that gave each of us the most pleasure when fucking in different positions and discovered when and how I could get deeper, stimulating the front or back wall of Lucy's vagina and applying different pressures and forces on both the head and shaft of my penis.
We both had other relationships during the year. I dated several girls, getting to fuck two of them and going almost as far with the others. Every one of them complimented me on my digital and oral skills. I had learned that, although girls pussies could look quite different, in general they seemed to react to similar stimuli and I never failed to get them to climax, usually several times in a session. One of them, Lauren, even asked who had taught me to eat a girl out as well as I did. I was sorely tempted to tell her I had practised my techniques on my sister but instead I just grinned.
Lucy settled for less variety, starting a steady relationship with one boyfriend called Greg, who by all accounts (because we would tell each other about all our sexual experiences) was delightedly enjoying Lucy's well-practiced blowjob skills on a regular basis, but failing to give her much satisfaction in return. I found it hard to understand why she stayed with him.