Well, it's my sister and my half-sister but it's only a detail. Actually, I start fucking my half-sister when I went to work for her father and used to spend a lot of time with her at the store. I found out she liked big cocks so I've made sure she took a peek at mine "accidentally". It was love at first sight. At the end of the day she was already sucking on it in the parking lot. My half-sister is my full sister's best-friend, and they talk a lot, mostly about guys. And she told my sister she was fucking a new guy, but didn't tell her it was me - her brother. It didn't took much for her to figure it out because when my half-sister started to give her some details, she immediately knew the guy was me. I've been fucking her too for about 3 years. Now I live in Fuckland when we get together.