I signed her up for both yoga and exercise classes. The Yoga was good for sex, she got a lot more limber and the exercise class got rid of that little...tummy fat. Besides her trips to yoga and the gym, at least twice a week we'd watch TV together with a couple of my fingers up her pussy for a half an hour as she exercised her vaginal muscles. We'd be sitting there and if mom forgot to clinch at least twice a minute, I'd yell clinch and pinch her nipple. I rarely have to remind her. "Sebastian! I am surprised! The stories we have heard led me to believe you were a sex fiend!" she said, before sending two hostesses scurrying toward the bar and the kitchen. "Perhaps, after you have eaten?"I grinned and squeezed her thigh. She smiled and squeezed back. "Call me Laiya," she said. I didn't realize how appropriate her name was until later."Tonight the theme of our entertainment is incest. All genuine and surprisingly popular with our membership. You have missed the first two. “Karen,” I asked while not slowing down, “have you ever eaten another woman’s pussy before?”My sister lifted her head just long enough to give a quick answer. “No.” she replied before she dove back in to licking Rebecca’s clit.“Why not?” I had to ask.“I just can’t,” she responded before re-attacking Rebecca’s clit with her tongue.For me, just knowing that my sister was doing something that she would not ordinarily do sent a chill through my nuts, threatening an early release even though I was. I only want to see you and Susie do it, Mark. You... you don't mind, do you?" For an instant he was too surprised to answer. Then his face went red, and a flush crept across his shoulders."The hell I don't mind! This is crazy!" Blushing hotly, he realized his cock was practically showing and jerked his pants up. "I'm not gonna go showing off my cock to the whole world -- and especially not to my own sister!" Oh, don't be a baby!" This time it was Susie's turn to be irritated as her pussy itched.