.You mean kissing with our tougues?" I asked nervously "No i mean Yes you big head!!" She said with a grin"I guess it wouldn't hurt if we..." she grab...ed me and kissed me i felt her tougue coming close to mine just as our step dad came out from nowhere."What the..KATIE . GET TO THE HOUSE NOW!" He yelled as katie ran off.He pulled me by my sweater and had me by my throat as he said through gritted teeth"If i ever see that again, I'll beat some sense into you, she's your sister for gods sake!" He. She continued to moan and begged me not to tell her husband or show him the pictures. I thought for several moments while I pummeled her ass with my throbbing rod."Tell you what," I said. "You come over and fuck me anyway I want, anytime I want when your husband leaves town, and I wont tell him or show him the pictures." That's blackmail," she exclaimed."Your right," I scoffed back at her. "And you can either agree to it or not, its your choice."She whimpered and started to cum, as I spanked. P.m , i took the day off so as to be relaxed etc,so i duly arrived that evening, they had one of those security buzzer things on the front door, i duly pressed the button and ally answered and said i'd find her in their kitchen , so on reaching the kitchen only to find ally bent stark naked over their kitchen table, " do what you want with me this weekend " please said ally , well i knew sex etc was on offer but i was not expecting this as such, but on seeing her like that i was hard in. I swallow."May I?" I ask.She gives her assent, or so I assume, by closing her eyes.I control my shaking hands as they go to the front clasp of her bra. I should not be doing this. I know I should not be doing this. I slip the clasp. This is madness. I look at her to see if the wrongness of what I am doing is apparent to her. But her eyes are closed. I'm surprised her eyes are closed. My hands go to her breasts. So warm. Oh good Christ how warm they are! "Any pain?" I ask. The expression on her.