Tommy didn't now what to say or where to turn. He spun away from the girl but she could still see his cock in the looking glass. His cock was still hard as a stone, despite the youth's discomfort at being caught.

It was far too big to hide it behind his hands. "You shouldn't just walk in the a guy's room, Sis," he mumbled in feeble protest.

"I wanna watch," she replied.

Tommy gulped, shocked. But then he began to grin. Tommy had often thought about his nubile kid sister when he was beating his meat and if the girl was naughty enough to want to watch him, why should he object?

Jacking off would be a whole lot more exciting with his sister looking on, he figured.

He turned back toward her and they exchanged a heated glance, like conspirators plotting a crime. Then she dropped her gaze onto his groin again. Tommy moaned. His cock-meat rippled as if her eyes were caressing him.

"Sure, Sis you can watch me," he croaked. "But you gotta show me your tits while I do it."

Belinda giggled and opened her dressing gown, revealing her tits and her cunt-bush, to boot. She arched her back, thrusting her tits out toward him. Her slender, shapely hips moved sensually.

"You can shoot on my tits, if you wanna," she rasped, her voice husky with desire.

"Yeah!" Tommy enthused. His prick was pounding at the prospect.

Kneeling behind the mirror, their mother was staring at the naughty siblings in fascination, looking at them as they looked at each other.

But there was no glass between them. Jenny knew that she should nip their incestuous game in the bud, stopping it before things got out of hand.

Belinda sank down onto her knees, bringing her tits level with her brother's loins.

Tommy shifted closer to her, trembling violently. His cock was angled up like a howitzer, ready to discharge a creamy volley into her face and onto her tits.