Lucinda's panic subsided as she looked back into the room and saw Steve urging Dawn up off his still-stiff cock. He put his hands on her firm ass and lifted, his big prick popping free of her wet pussy as she came up.

"Suck me!" he demanded in a low growl. "Lick your own cum right off my dick and let me shoot my wad right down your throat. Hurry up about it, Sis. I gotta came soon. My balls are on fire!"

A look of joy spread over Dawn's pretty face. She nodded her blonde hair teasingly and moved back a little on the bed, so that she was on all fours just above his dripping prick.

"Mmmmmm, Steve, darling, you're so fucking nasty!" Dawn hissed happily. "You really know how to turn a hot cunt like me on and keep her on, you filthy little fucker!"

Lucinda's shocked mind could barely function. She would have sworn that nothing could have gotten to her after seeing what Steve and Dawn had already done tonight, but hearing her big sister talk like that really shocked Lucinda.

And what Steve wanted Dawn to do to him! Lucinda could not believe her ears. No one would be so depraved as to actually do the ugly things that Steve wanted done.

But now Dawn was showing her younger sister otherwise. The luscious eighteen-year-old was cooing over her little brother's glistening cock expectantly. Her hot tongue flicked out, wiping its way around the wet, red tip of Steve's dick.

"Ohhhhh," Lucinda sighed, fearing she was going to be sick to her stomach.

The feeling passed in seconds. The brief threat of nausea was quickly replaced by a feeling Lucinda was growing more and more used to by now – the rush of hot, gripping lust.