"I love the taste!" she said, with a giggle. "Yummy!" Then she added, "I wish Martha had a man. I feel so sorry for her. She's always alone."

Frank chuckled. "That sister of yours must pass a hell of a lot of time playing with her pussy!"

Above them, on the other side of the grate, Martha blushed.

Claire continued sucking and fingering Frank's cock and it wasn't long before it started getting hard again. Martha's pussy was sopping wet as site watched her sister suck on Frank's cock.

Claire finally pulled her face away and looked up at him. "Want more?"

"Dog-style!" Frank grinned. "Get on your knees!"

Her eyes wide with amazement, her cunt trembling with lust, Martha watched as Claire knelt on the edge of the bed with her head down and her ass up in the air.

Frank left the bed to stand behind her. Claire wiggled her ass and peered at him over her shoulder.

"Come and get it!" she crooned.

He moved forward until his hairy belly was rubbing against the globes of her ass. He slipped his hand down to finger the lips of her cunt. Fisting his cock, he rubbed his cock head up and down between her hairy pussy lips.

Claire groaned as he positioned his cock head in the socket of her cunt hole.

"Oh, God! That's good!" she said.

A moment later his hips lurched forward and he sank his cock all the way inside her steaming cunt. He began pumping, his ass bucking back and forth as he drove his cock in and out of her juice-drenched pussy.

Martha feasted her eyes on the scene below. She thrilled at the sight of Claire kneeling over like that, at Frank mounting her from behind. The animal-like position made her shake with excitement.

Soon Frank was rasping, "Hold on, baby! I'm going to blow!"

A moment later he began bucking his ass in frenzy as he shot his load into Claire's cunt. Once more Martha imagined the thick jism spurting out of her brother-in-law's cock to splatter inside Claire's grasping pussy.