His powerful forelegs clamped her heaving hips in a tight embrace pulling her to his furred underbelly and preventing her release. With each thrust of his canine hips, his cock drove deeper into her belly causing her to whimper with the pain of having this monstrous dog cock search out the neck of her womb.

The Doberman was her master now in more than just the physical sense. She had invaded his territory and offered her sex to him. The pack instinct had taken over, this was not just about procreation as far as the animal was concerned, this was about authority, this was about being alpha-male, this was about dominance.

Duke, as his human counterpart had named him, was alpha-male in the pack of three dogs that guarded the two and a half acres of prime Californian real estate. It seemed that a ten-foot high wall, instead of being prevention to entry, was a challenge laid down to any with a spirituous nature. Duke, and the two Doberman- boxer crosses were the last resort.

A silent infrared trigger set them free of their pens to seek out and subdue the trespasser. They had perfected the art of search and hold, trapping the unwary intruder until humans came to take the person away. It worked most of the time, but occasionally, the wait for their master took too long. Boredom would take over and the dogs would have their fun, often with disastrous results and a body to be disposed of.

He had made his point with this woman. Without actually fucking her until he knotted with her, he had made sure she knew of his dominance. He bit her shoulder in a final act of aggression and allowed the two other dogs their way. He knew their immaturity would prevent them from consummating any union, but they had to learn. Although it is an instinctive thing with animals, experience counts.

He withdrew from her white thighs, negligently noticing the red welts where his claws had raked her skin. He signalled to the waiting pair that she was theirs to play with and stood by to watch.

Very soon, the brindle was lapping away the seminal fluid that leaked from the bitch’s labia. Bruno was pleased to see that the brindle was becoming an expert in bringing these bitches to screaming fits with the powerful strokes of his tongue. It was a familiar scenario. A human woman breaks over the wall; trips the sensor and the three of them get to have fun with the intruder. Rarely would his master intercede in these episodes, believing that she deserved the fate she was receiving.

While the brindle was performing earth-shattering fellatio, the white had forced his cock into her mouth. It was quite usual for their victim to display fear or unwillingness to comply with this act, but they all succumbed to it in the end. The white had a reasonably long dick and could quite often get them to throw up on his semen as it splashed against the back of their throats.

This woman seemed to be enjoying herself. Although this wasn’t a necessity as far as the three were concerned, it did make for an interesting session if compliance was granted. Having turned over onto her back, She grasped the whites cock at the base, just behind his tennis ball sized knot and was sucking avidly.

The feeling for the white was almost the same as being knotted and there would only be one outcome from that. Sure enough, in very little time, copious amounts of dog come were slipping down her throat. She swallowed most of it and licked the throbbing member that she still had grasped in her hand.

The brindle had a penchant for this treatment as well. Unfortunately, it was rare for one of the bitch’s to want to, or be able to oblige. No problems to Duke, the brindle was the most junior of the trio and got whatever was left. If that meant he didn’t climax, well so be it and that was just tough.

Tonight’s entertainment was up for it though. As soon as the whites knot had receded, the brindle let her know he was in the mood for some of the same by placing his ready cock in her face. Bruno and the white sat and watched as she slurped and manipulated the brindle’s dick, until he too sprayed her throat with his seed.

Bruno, thinking that perhaps he might just fuck this one all the way, calmly walked over to the prone girl. Her clothes had become shredded in the struggle to avoid capture or were now left discarded on the grass where Bruno had ripped them from her body in order to get at her sex. He smelled her, taking in her scent. His synapses told him she was fertile, healthy and very aroused.

Her organs relayed messages in synaptic responses in his brain, telling him that she was not yet satisfied, that she wanted more, that she was not yet pregnant. That was how it should be. His own sex with her had been more to subdue than impregnate.

He turned her over so that she was once more laying on her front. A quick check over revealed no damage to her apart from a few minor scratches. Grabbing the back of her neck in his powerful jaws, but being careful not to grip too hard and break her skin, he dragged her to their den. The girl whimpered and cried out, but didn’t resist and even helped by crawling across the grass.

At last, they reached the shelter of the brick kennel with its warm bedding and clean fresh water. The girl drank from the stainless steel bowl; slaking her thirst and washing out the taste of dog come from her mouth. She seemed to know that her place was as part of the pack, at least for the present. Exhausted, the girl curled up in a corner on some of the straw bedding and was soon asleep.

During the night, the brindle was allowed to practice fucking the girl. She was encouraged by nuzzling and growling at her to suck him until he was good and hard. The dog returned the favour, licking her sex until she quivered and lubricated her self. The brindle mounted her, grasping her waist in strong forelegs and rammed his cock deep inside her.

It didn’t take too long before his thrusts took on an urgency as his climax built. In deference to the pack leader, he kept his knot from entering the willing woman’s vagina. He shot his load, liberally spraying it inside her and then continuing his emission over the creamy white skin of her arse. Instinctively, he cleaned her skin, licking all traces of his sex from her. The result was that she came with force, soaking his muzzle with her come. She slept until the dawn.

The gardener always let the dogs out to exercise in the morning. Given the freedom of the grounds, the three dogs would chase around until they lay panting and ready for breakfast. This morning was no different; he opened the pen gates and gave the dogs their freedom. Bruno hesitated and preferred to stay with the girl. He didn’t want her to leave the pen and be taken away with the gardener.

"Well, what you got there then?" The Gardener was accustomed to finding intruders who had had the attentions of Bruno and his boys. He wasn’t used to finding them sleeping with the dogs though.

She woke, stretched and yawned in one fluid motion, then realised she was looking at a fellow human from the dog pen with few clothes on. She shrank back, trying to make her self as small as possible. Neither Bruno nor the Gardener could guess what was going through her mind, but watched fascinated as her fear showed in her eyes.

"Please leave me alone." She croaked. "I want to stay here in the warm." The pleading was all too evident in her voice, even Bruno understood her need to stay in the pen were she felt safe and secure.

"I’ll bring you some food then. Can’t have you starving can we? I mean, even the dogs get fed well here. We’ll just call it our little secret shall we?"

She nodded her acceptance of the food and complicity in her stay. Later, food was brought by the Gardener as well as some bottled water. She was too busy sucking Bruno’s giant cock to really acknowledge the delivery. The Gardener withdrew, leaving her and Bruno to their pleasures.

Food was brought twice daily from then on. The Gardener not once commenting on her situation, but accepting that she was quite happy and well.

Bruno checked his new mate on a daily basis as well. Every day he would smell and lick her sex, checking to see how she fared from the constant fucking and administrations of the three dogs. Time past and in what seemed like only a few days, almost a month had slipped by.

A regular routine settled on the four. Each day she would allow the dogs to fuck her, clean her cunt and she would suck them until they shot their load into her mouth. She showed no sign of inhibition, the dogs availed themselves of her, using every entry into her body, but never tying with her. The girl thrived and gave of herself as much as was given to her. She seemed to have no bounds to her capacity to love these dogs until they were sated.

The day dawned, bright and sunny as usual under the Californian sky. Breakfast was eaten and the dogs had their usual romp around the gardens. Bruno returned to the pen ready to lie in the girls lap and have his customary nap. The other two usually gave him a little time alone with the girl in the mornings.

Her smell had changed. Something undercut the usual human stink of sweat and body odour he had become accustomed to. This changed scent excited his olfactory senses and elicited a tingling in his balls.

He checked her over and discovered she was menstruating; this was what he had been waiting for, although he wasn’t aware of it. Bruno could no more help himself than stop his actions. Without any preamble, he shoved his nose into her groin and drank deeply of her aroma. His excitement mounted all the time. Involuntarily, his cock exited the protective sheath and swelled with blood.

Bruno licked her, his tongue tracing between her lips and over her clit. She shuddered in her own excitement, probably knowing what was to happen in a fundamental and animalistic base sense.

She turned around and knelt on all fours, offering her sex unhindered to him. Bruno continued to excite her with his tongue, hearing her breathing grow ragged and gasps escape from between her clenched teeth. She was ready to receive him and Bruno had reached the point of readiness, with his cock throbbing and dripping, fully extended from its furry haven.

Bruno mounted her, but was disturbed by the white and brindle returning to the pen. He snarled a warning to the eager pair, which told them, in no uncertain circumstances, that their presence was not welcome. They backed off, grovelling in deference to his superiority.

Once more left to them selves, Bruno and the girl began the prelude to sex again, raising their readiness until the point of orgasm. Once Bruno was certain she was ready, he mounted her and tried to shove his entire dick into the waiting fuck hole. His aim was off, nearly all of his cock slipped effortlessly into her anus. Under normal circumstances, she would not have minded and backed onto him, but today was to be different; they both knew what they wanted.

The girl pulled forward, grabbed Bruno’s glistening and extended cock, and then guided him into her vagina. Bruno launched his tool into her, breaching the neck of her womb in a powerful thrust that took her breath away. He clamped her waist and began to pound into her, each stroke getting him deeper until his knot banged against the outer lips of her labia.

He was getting very close to reaching his climax and could feel her readiness to accept the entire animal dick that was nudging the opening of her cervix. Bruno thrust longer and with less force, but more determination, suddenly; he felt his knot slip between her contracting muscles. He was fully enveloped by the tight sheath of her sex and the muscles contracted around the base of his knot. Bruno could not move now without doing damage to one or both of them. Instead, her own internal muscles took over the rhythm and massaged his tool over its length, positioning the head and forcing it into her womb.

Bruno exploded; his semen streamed into her, filling her womb until her belly extended with the influx of his fluid. She held him with her muscles, still massaging and coaxing out every last drop of him. For several minutes, Bruno continued to pump his seed into her, then, when his waves of orgasm receded, she held him trapped inside her. They waited for about ten long minutes until her muscles relaxed and Bruno’s knot diminished enough to let them separate.

Very little flowed from her. Dutifully, he cleaned her while she curled up in a foetal position, totally sated and pleased with herself.

Bruno and the girl mated several times during the day, but without the same effect. They knotted, but his semen was ejected as soon as they parted. Bruno would not allow the other two anywhere near her and stood guard over her, issuing a warning to them and the Gardener.

His nose told him she had become impregnated, that she was carrying his offspring. He would not leave her side for more than a few seconds until she bore four small puppies.

The girl stayed with Bruno for another year or so, producing two more litters of puppies that displayed remarkable intelligence and height. The Gardener sold these pups and made a fortune from them. Eventually, the girl was discovered by a vet who had come to check over the animals she was taken away from the pen in a van with blacked out windows. Her power of speech had all but left her and she preferred to walk on all fours.

Bruno was put down. The Gardener was prosecuted under the indecency act, the girl was never seen again, but a new breed of dog sprang up. It had this almost human capability to understand what was said to it by the owners and displayed a tendency to stand on its hind legs.