I felt dizzy and weak as I stared at the erotic beauty before me."Think about getting out of your little cage and sliding yourself inside me. Lean clo...e now; I want you to be able to smell my feminine scent. Scientifically speaking, pheromones emitted from a woman's private parts do more for a man's arousal than purely visual stimulus. So breathe deeply and take me in. Good boy. Is your penis beginning to swell? Yes? Wonderful, let me see so I can take my readings."With that, the Nurse dropped. Katie looked back over at me and looked me up and down and stared at my cock a bit longer then shrugged her shoulders as she walked up to me and pulled my shorts down to my ankles and took my cock back into her mouth for a few more seconds. Pulling my cock out of her mouth again said told me to lie down on the floor. I did as I was told and she got between my legs and started to suck my cock for all it was worth. I looked up at my sister and smiled and she walked over to me and straddled my. My energy was at an all time low, but my satisfaction, high.Gemma crawled over me to John."He did good, didn't he?" she asked."Yeah, he tasted great, so did you Sis."?????????????????????????????????? !No - I misheard!"What did you call her, then?" I asked, almost afraid of the answer I might get."Sis, why?"My mind went blank, Jesus, I had a brother and sister here - I'd sucked off his sister and she had sucked off her brother - and now both had sucked me off !My prick immediately got hard at. I heard her reach back in and pull out another item. The distinctive *POP* of a cap being taken off, and then the feeling of something cool being poured over my cock. Then her hand wraps around me and begins to slide up and down over my now slick dick. Her hand moves up and down the length of my shaft, causing me to moan loudly through the tape covering my mouth. With her free hand she begins pressing a finger against my asshole, teasing the opening while she fucks me with her hand. My cum.