He broke the lingering kiss. "Mommy, would you stroke my cock?"
Without an answer, she dropped her hand down and began to do just that, running her fingers along its length - probably 8 or 9 throbbing inches - then lightly jerking him off.
"Oh god, that feels so good," he said, then leaned his head down and again began to make out with his sexy fuck-toy of a mother.
After a few minutes of that, he was unbearably horny - as, he imagined, was she. With one arm, he swung his mother over his body, pinning her under him. She gasped at his strength, though, of course, she weighed barely 100 pounds. But instead of fucking her right then, he got up and stood next to the bed.
"SIt up," he commanded. She did as told, her huge tits bouncing as she did. She brushed the hair out of her face and stared up at him adoringly. Sitting like that, with her hands in her lap, under those incredible tits, with her petite body perched on the edge of the bed - she looked nothing so much like a teenage girl with huge tits, waiting for her reward. His cock, huge, throbbing and almost purple, stood hugely erect just inches from her face, a drop of pre-cum dangling from its tip. Instinctively, she leaned forward and licked it off. He shuddered.
"Suck me, Mommy. Suck my big prick."
"Yes sir," she said in her little girl voice, and slowly began to run her tongue along her son's impressive girth, then plunged her mouth over the cock and began bobbing her head up and down on it. He moaned with pleasure and placed both hands on the back of her head, encouraging her to take more and more of it into her tiny mouth. Soon, they were both moaning uncontrollably. With one hand, she began to tweak one turgid nipple; with the other, she reached down and started to diddle her throbbing clit. It was the most turned-on she had ever been.
"Suck harder. Mommy," he commanded. "Mouth-fuck me."
"Mmmmmm," she mumbled with a mouth full of her son's cock, and began to speed up her sucking. After a few minutes, she came up for air.