Rex hesitated. Being only a dumb brute, he knew no such emotions as envy or jealousy, yet the canine equivalent caused his tongue to tingle and his cock to throb. He was tempted to bound into the room, yet sensed that the master might not welcome his presence. Although a whole howling pack of horny hounds might rush in pursuit of a bitch in heat, she could accommodate them only one at a time. And Debby, quite obviously, was already spoken for. And yet her cunt, from where that delightful aroma spread so tantalizingly, was unoccupied. It was a puzzlement to the dog, although he knew from happy experience that human bitches were far more inventive and imaginative and adaptable than the canine bitches.

So Rex hesitated. But his prick was thundering, his tongue slobbering. Warily and nervously, he moved into the room and began to slink up on the girl. His haunches were lowered, as if he were sneaking up on a juicy bunny – but no bunny had ever been as juicy as Debby's pussy.

And, although wary of his master, Rex had an advantage. Being only an animal, Rex had no idea that bestiality was naughty. To Rex, fucking was the most natural thing in the world, and he advanced without inhibition…

Debby had been using only her tongue, to begin with, licking up and down her daddy's long, thick cockshaft, tonguing his bloated balls and slurping on his cock-knob. His piss hole continued to ooze with pre-cum and the cum-hungry teenager lapped it up greedily, murmuring with the joy of it. His whole cock was slippery with her frothy saliva. His jism ran into that wet fluid, thicker and creamier, and Debby eagerly tongued it up as it ran down his prick.

Then she licked up to the tip of his cock and turned her radiant face down. She pushed the tip of her tongue right up into his piss hole, causing Frank to jerk and gasp.