He had encouraged her to masturbate and show him and overcoming her initial shyness she had loved his gentle love and the freedom to play mentally and...physically in his company. They were devoted to each other and difficult though his severe disability had become life was good for them both from the strong love they had together.He had grown over the years to be a distinguished professor and she had loved to share in his work and to be credited with co-writing and presenting papers and. Now we'll have some real fun."I did as she directed, got on my hands and knees on the bed. I wasn't sure what to expect. Given how rough she was fucking my face, would she come at my ass like a battering ram? Instead, she walked away to the bathroom. I heard water running and soon she was back with a warm washcloth which she rubbed against my ass. "Gotta have you kissing sweet," she purred. She got up on the bed and leaned forward, kissing and licking my backside. She ran her tongue up and down. I really went to work on this cock. I just had to have his cum load. He just grunted and pushed his cock further into my mouth. I swallowed all I could and licked his shaft. He started to grunt even louder and fuck my face quicker and then he just exploded into my mouth. I swallowed as fast and hard as I could. He eventually slowed down and I finished him off. I loved the feeling of this big cock in my mouth. When he was finished, he pulled his cock out of my mouth with a plop. My mouth was. "Ben, I'm leaving the car keys and money for movie rental and a pizza for Saturday night. You're staying home with Lori, no company, no going anywhere except to pick up a movie, and you do what Lori wants this time. She gets to pick the pizza and whatever else she wants to do. She's your sister and you usually get what you want. It's her turn this time."Mom's back is to Lori who pulls down her tube top to flash her boobs at me. She's turned into such a tease but I do love it."It's really nice.