He did have a big dick, she thought wonderingly. A really big one.

Dave slipped his hand under the sheet. He ran it up his sister's naked thigh and pressed his finger into the still-moistened slit of her pussy.

"Well for starts you could take off this sheet!" he suggested huskily. "Always did want to see you naked."

"Dave!" Debby said sharply, staring at him in horror. "How… how dare you! You can't!"

"I can do anything I want to," Dave interrupted. "Unless you want me to have a little talk with Dad."

Debby bit her lip and stared at him helplessly. Without waiting for permission, Dave pushed the sheet away, leaving her naked.

He seemed in awe of her body. His eyes widened as he saw the size of her, enormous firm breasts, the color contrast between their whiteness and the red circles of her nipples. Gradually his gaze moved downwards, taking in her slender waist, lithe hips, long legs, the fleecy brown triangle of her cunt.

Dave grinned and slipped his finger into the clinging lips of her pussy. Expertly he pumped it in and out of her hairy snatch, jacking her off.

"Unnnhhhh," Debby moaned. Within seconds her cunt became extremely hot and wet. Her nipples stiffened with desire; her pussy walls sucked around her brother's probing finger.

Debby didn't want to fuck Dave, or be blackmailed, but she couldn't help it. She'd been so close to cumming when he'd entered the room. His big dick was rock-hard now, and looking at it bulging in his shorts turned her on. Deep down inside she already wanted him to fuck her.

"Stop it, Dave," she whispered. But her words were meaningless, and both of them knew it. "Unhhh no… don't do this, not to your sister… ahhhhh, Dave…"

Dave withdrew his finger from her sopping pussy and stood up next to the bed. His expression was quite serious now. Silently he pulled down his jockey shorts. His heavy cock bobbed out, standing straight out before him like a battering ram, jerking stiffly with its engorgement of blood. The head was fat and crimson, and the cum drooled freely from its tip.