"Why don't you roll over and let you nasty big sister really say good morning to you."

Mark didn't have to be told twice, rolling over onto his back and kicking the sheet off to expose his incredible cock, which was already standing at attention in anticipation of his big sister's very eager mouth. I sat up and, after first bending over to give Mark a long passionate kiss, put one of my hands over to the other side of him and began to slide my tits back and forth across his face, keeping them just low enough that my nipples would graze his outstretched tongue, but high enough that...