I leaned over my sister, put my hands on the bed beside her head then fucked her. She watched my face intently while our bodies slapped against each o...her, my cock was plunging deep while our stomachs rubbed and chafed. Tiffany smiled with lips and eyes then rolled her head to the side and grabbed my waist, pulling me closer, urging me to bang her harder. Her big tits shook and quivered each time my nuts slammed against her. She lifted her feet off the floor and crossed her ankles over my ass.. Before I could even answer, she added, “You seem to like touching me down there, and it feels nice, so maybe you could do it to me, and then I could do it to you.”I wasn’t all that fussed on having Tina go down on me, but I really wanted to taste her, and I said, “Um, what if I, umm, you know,” pausing, stammering, “in your mouth.”Tina just smiled and said, “I don’t know. Katy showed me a book that said some girls like it. I’ll never know until I try it.” I looked down at my own crotch, and saw. Bingo! Hard-on! We ARE like animals," he said smiling.I was about to tell him I would finish off for him, if he wanted to start it, when I felt a familiar feeling."Shit!" I shouted. "Literally! I haven't crapped in 2 days and all of a sudden NOW it decides to come calling. I can't wait." I said as I ran back across the cold room.As I just made it to the john I heard Bill say to no one. "Man, could I ask for a sexier babe, or what?"If he knew what my getting my bowels back to normal might mean. Oh god she is so beautiful, she's gorgeous."I heard Dave groan softly and then looked just as he shot his load. It was then I understood mom turned him on. I hissed, "Damn Dave! That's mom in there!" Up until that moment he had no idea I was there. He gasped, "Oh damn Wes, please don't tell on me." I started to say, "don't be silly! Who would I tell?" But mom called and said, "David honey! Come here please... I need to talk to you dear." so all he heard was 'Don't be silly! Who..."I slipped out.