"Oh!" she gasped in surprise.

Cindy had placed Robert's cock against her palm, and instinctively she tried to pull away. Instead her fingers closed, and she had a handful of his throbbing young cock.

Robert laughed and Cindy giggled, then Kathy felt him moving his cock in her hand. Ho was fucking her fists, and she couldn't get her fingers open. Kathy's fingers seemed to tighten up of their own free will, and she gasped with shame. His cock throbbed as he fucked it back and forth into her fist.

"She's holding it, Cindy," she heard Robert say excitedly. "She's holding my cook!"

Kathy suddenly made her fingers relax. "Damn you two," she said harshly. "If you don't untie me this minute, I'll… I'll…"

"You can't do anything," Robert said, he and his sister coming to stand at her sides again.

"I'll tell," Kathy said. "I'll tell your parents!"

They showed no fear of her threat.

Cindy reached over her thighs and began pumping on her brother's cock, pressing it against Kathy's thighs again. Kathy shivered from the throbbing touch. Her hand seemed to itch from holding his cock, and she balled it into a fist, but that made the sensation worse. Her cunt was very wet and quivering, and her tits were swollen. She tried to will her cunt to stop, closing her eyes against what she was seeing. But she could still feel his prick on her thigh.

Kathy opened her eyes.

Cindy was pumping on her brother's cock faster now and Robert was making gurgling sounds. He arched his hips forward, his balls against Kathy's thigh. He was dripping more pre-cum from his piss hole, and Kathy realized he was on the brink of coming.

Robert placed a hand on Kathy's leg, near her knee. His fingers were digging into her flesh as he grunted. Cindy now gripped ha brother's cock hotly as she jacked him, pumping faster. Kathy looked into Cindy's eyes as the young girl made soft cooing sounds. Cindy's eyes were almost glassy as she stared at her brother' cock, her fist pumping.