As we worked on her problems, I noted that at various times, Caitlin kept walking past the room where we worked. While I had only glanced at her, each...time I was greeted with a shy little smile.Taking a break, we went out on their porch and sat in a swing drinking tea. It was a very warm humid evening and as we talked, she seemed to be very nervous. Her hands kept fumbling with her blouse buttons as she spoke. Now, I don't know if it was intentional or accidental, but the center button right. They even called in a neighbor to take a photo of my date and me with mom and dad.We didn't go anywhere fancy for dinner. He took me to Denny's. Needless to say, we were the only people dressed for a prom eating there. I was mortified, but luckily, I didn't see anyone I knew. During dinner, his hand found its way onto my leg through the slit, and onto my panties. I was scared as he rubbed me. He found my button, and I jumped.His hand was on my panties most of dinner. We didn't talk at all.Just. The he told me to come over and suck one of her tits and i said thats my sister and he said i dont give a fuck do it or i will tell your dad you broke my window,so i got up and went over and started to duck her tits and she was crying even louder now and i felt a little sorry for her,the while steven was sucking her tits he move his hand down to her skirt and he unbutton it and unzipped it and it fell to the floor and now all my sister has on is a pair of pink panties and he was rubbing her. I then had her stand over me and above me as I looked at her perfect pussy and ass, she was totally waxed for me now, again, she followed orders. No longer the shy, conservative little perfect preachers daughter, along with me in her bedroom, her parents bedroom, her kitchen, her living room, my house, my hotel or my car, she was a 100% total cum whore. I loved it and so did she. I made her play and finger her pussy until she cum, watching her and watched as her knees went weak. Finally I.