"Oh, fuck me, Jimmy! My little pussy wants your prick so bad? Unngggh! Fuck my pussy, Jimmy, fuck my little pussy? My pussy waits to cum!"

For several seconds Karen stood motionless, her mouth hanging open in shock, unable to believe her ears. But the moans and grunts continued unabated, and soon she recognized her brother's sighs mingled in with them.

There was no question about it, her kid brother was fucking some girl in the living room right now!

Don't look, Karen told herself. She took another step toward her bedroom, knowing full well that the only decent thing to do would be to lock herself in the room until Jimmy and the girl were finished.

But then her curiosity and horniness got the better of her. Feeling utterly ashamed of herself, the big-titted big sister turned and tip-toed down the hall again, until she reached the end of it, until she could see all of the living room.

A big, musty old couch was pushed against the far wall. That was what Jimmy and the girl were fucking on. Jimmy was sitting on the center of the sofa, completely naked, his fingers pressed into the girl's waist. The girl, a slim blonde about Jimmy's age, had straddled him in the woman-on-top position, with her knees planted on the cushions to either side of Jimmy's hips.

"You've got a tight pussy, Kathy!" Jimmy groaned.

"Oh, keep fucking me, Jimmy!" the girl, Kathy, gasped. "Unngggh! Keep fucking my pussy, my pussy wants to cum!"

The girl was wriggling and humping her round, little fanny like a dervish, holding onto Jimmy's shoulders as she pumped her buns up and down, slamming her wet, sucking pussy onto the base of Jimmy's prick.

Oh, God, Karen thought. She just stood there, her eyes bulging, a fire starting under her panties as she stared at her kid brother's cock. Oh, God…

Jimmy had a big one. A really big one, one of the fattest, longest boners that Karen had ever seen. He was such a skinny, boyish-looking kid at eighteen, and now she could see that his prick was nearly as oversized for his skinny body as her tits were for hers. The long, meaty truncheon rose out of his cock fur like a baseball bat, glistening with Kathy's pussy juice, disappearing and reappearing as Kathy pounded her throbbing cunt on its base.