Embrace the experience
They say true freedom is taking things for what they are, not being weighed down by doubts and living in the moment. I try to live by those words. So the first night my sister and I felt an attraction and had sex, we just accepted it and went along.
She's older than me by eight years. With this whole mess I needed some place to stay to cut expenses, and she had just broken up with her boyfriend, so figuring she might use the company, I offered to move in temporarily, while this thing blew over and we could continue our normal lives.
I did have a crush on her beforehand, but strictly platonic. She was always kind of the black sheep of the family, always very open about her ideas and her sexuality. She estranged herself from our parents after starting to work nights as a stripper to make ends meet during college. I always stayed in touch with her, but our family didn't take gladly to her reputation, having many boyfriends and all. She got herself a boob job and suddenly she was like my dream girl: petite, athletic, covered in tattoos.
When I moved in, and both of us being single, it only took a few beers and some intimate talk for both of us to give in and do something about our horniness... but we didn't expect to be so hooked. Now I feel effectively addicted to her body, and she's very casual about "being my whore" since I'm just her kind of man (I guess she means much taller, athletic enough to keep up with her, and large enough for her taste). She's quite filthy and experienced, capable of taking the lead and make you cum in 5 seconds if she wants to, or be completely submissive and let you have her way with her. We can't keep our hands off each other, we do it almost every day and can't have enough. She's on the pill, but to be sure we use mostly her ass, and she's crazy for it. Just looking at her gasp for air and tremble when she cums, makes me cum hard as well. We cum together a lot. So I don't stop to think about the implications too much, just living in the moment.