The Filthy Festival - Part 4 - Brian's loose bowels

A loud fart came out his daddy's rear as he jumped up with shock and turned around.
"Billy?" he whispered, "what are you doing down there?"
The brown-faced foxcub smiled toothily, showing brown stains between his teeth, "I'm having fun, dad." he said with the youthful optimism of his ten years of age.
"You look as if you have been burrowing around down there, you filthy cub!" Brian exclaimed, taking in the sight of his son's body covered in filth, some parts stained deep yellow, some parts covered with bits of toilet paper, and his entire head and neck region covered in brown and black sludge and bits of various furs' scat. The perverted father felt his dick throb once, twice, thrice as the sight stirred a deep pleasure within him, seeing his boy so utterly defiled by others' waste.
"Just a little, Daddy, mostly I've been playing around with my own stuff, and then a stallion almost drowned me with his piss! And then, and then.." the foxcub too excited to speak properly, "and then these two cute cubs came in together and peed on me together, and one of them, a wolf, pooped so much onto me I thought I wouldn't be able to breathe again!"
"Oh, you naughty naughty rascal! I saw those cubs leaving here and thought about you and chose this portapotty. What luck this is, what are the odds of me finding you down here?" he asked retorically, as he knew the odds were incredibly low. It was almost as if the gods of filth had heard his grumbling prayers for his son's muzzle to empty himself into. 
"Odds?" the cute cub asked.
"No matter, kid. Get your mouth up here right this instance, I definately have something for you to eat!" the horny father commanded, sitting down and using his hands to spread open his asshole.
Billy was greeted with a waft of strong musk as his daddy's unwashed asshole winked to him above. He stoof up in the mound and his hungry mouth found Brian's pucker and he started kissing and licking all over it. The musk was powerfull and ripe, his daddy having slept a few more hours in the sauna-like tent and strong-tasting sweat was all over his bottocks, his crack and his sphincter. 
The little cub-tongue felt like a heavenly angel caressing his sweaty behind and Brian moaned with pleasure as his son licked and slurped beneath him, the stink and the heat of the portapotty forgotten as he lost himself in pleasure. 
Having emptied his bladder so completely earlier, the perverted father started groping his sheath, coaxing out his already hardening erection. The thick slab of foxmeat quickly stood to attention and he let his hand caress all 8 inches of the bloodred rod that was quickly forming a bulbous knot, stroking gently in rhytm with his son's slurps and licks from below.
Billy was truly in heaven, there was no hotter place on earth than having his muzzle deeply buried in his father's musky behind, his little foxdick spasming in the warm air, his small paw stroking it with a sensuality betraying his age.
It took him no time at all to clean off the sweat and the musk covering his father's rump, and he soon gave all his attention to the musky pucker directly above him. He licked and prodded it with his small tongue, and was rewarded with it yielding to him and his tongue delved deep into his daddy's ass.
He lapped and slurped with gusto, alternating between sticking his tongue in as deep as possible and then sucking on the musky pucker trying to help Brian relieve himself, all the while touching and stroking his dicklet in the fetid air.
Brian was gently moaning as his asshole got best tongue-job in ages, his son obviously turned on and giving his best at pleasuring his daddy, trying to coax him into giving him a filthy meal. His stomach, momentarily ignored, grumbled loudly, and the older fur could feel himself getting ready to feed his naughty son. 
The hard lump and the taste of feces on his tongue, told Billy that his meal was getting ready for delivery, and he hungrily attacked the musky pucker by latching his muzzle onto it at sucking as hard as he could, a loud fart bubbling right into his mouth, getting him hot and bothered with the nasty taste of his daddy's innards spreading over his tongue and being forced out his nose.
The perverted fox stroked his thick cock as he groaned and pressed down, and felt his son's tongue pushed away by a thick piece of stool.
Billy could feel the massive turd exiting his daddy, somewhat surprised that something this solid could come out of him compared to the diarhea-like quality his farts had. He murred in pleasure as a thick snake of shit travelled into his muzzle and kept sucking the asshole feeding him.
Brian forced his sphincter closed with a pained grunt, not wanting to overwhelm the cub attached to his rear. He looked down to see his brown-faced rascal eagerly chomping and chewing through the thick turd that had forced its way halfway down his throat. His little paw rubbing his, for his age, impressive erection. It was hard to see down there, as the cub was so covered in filth, but the perverted dad was sure he could see a glistening of pre from his son's dicklet. He turned his attention to his own turgid member, his paw gliding all along its 8 inches, squeezing his fat knot as he imagined burying it in Billy's behind, and getting ever hornier from the sounds of his son munching down his waste. 
The sounds of squelching and chewing, cute coughs and gags and high and low-pitched moans could be heard even outside the portapotty, but both of the filthy furs were past caring and their lust drove them closer to the edge together. 
Satisfied that his son had chewed through a sufficient amount, Brian reached down and pulled him upwards by his filthy ears, almost too slick to hold onto.
The foxcub forced down the last of the turd in his maw with a loud swallow and assaulted his daddy's hole yet again with his tongue.
"Unfff, ohhh, gawd boy, get that mouth ready, I don't think you have to chew too much from now on," Brian said, his stomach rumbling, as his asshole winked a couple of times before expelling a slosh of runny beershit.
Billy was fast to get his mouth close over the pucker, and was rewarded with a fast-moving torrent of filthy waste with small clumps mixed with liquid shit that was shot down his throat before ending in his stomach. He kept his head turned up and simply relaxed his throat and swallowing, just like when daddy was deepthroating him, to keep the shit inside him. 
The taste was as awful as it was delightful, and his cubdick swelled in size as he gobbled down mouthful after mouthful, his stomach gradually bloating out again just like earlier in the morning, as his stomach was filled up with his father's nasty, reeking beershits that flowed out of his asshole like some kind of river. Only his experience with such filth and his extreme levels of horniness kept his stomach calm and let it be filled up.
With a torrentous and blubbery fart the scatty assault stopped and Billy was panting from lack of air as his paws stroked over his small foxdick in a blur. Brian was mastrubating fast as well, the incredible pleasure of emptying his bowels into his son bringing so close to the edge that his 8inch member was spurting precum all over the walls of the portapotty. He felt a hot breath of air on his pucker and he came even closer to the edge as his cub now licked all the nasty filth away from his spent asshole, gliding in and out the folds of his pucker, each movement of the agile tongue sending shivers directly out to his dick.
Suddenly he stood up, turned around, and reached down into the hole, forcing his son to stand up gingerly at the very top of the mound of filthy toilet paper and scat to face his daddy's fat dick. 
It was unceremoniously stuffed deep down his throat, and Brian rode his cub's muzzle like a fleshlight, his turgid member travelling deep down his throat as he humped away like a goddamn bunny, trying to expell his seed down that tight orifice, while his paws kept a close grip on the filthy headfur.
Billy sputtered and gurgled as the thick foxmeat was forced down his throat, ejecting spurts of thick precum to ease its passage. His paw kept stroking his own dick lighting fast and he came simultaniously with his dad whose knot scraped over his teeth as it tried to gain acces.
The foxcub moaned out loudly as he felt his dad's fat cock swell down his throat and send mancum directly into his stomach, and his own dick spasmed again and again sending boycum squirting onto the lower walls of the portapotty. 
Brian didn't hold back anything and forced his dick deeper and deeper into his son, his knot bruising and bleeding from the contact with his filthy fangs, he cared not and pressed on, almost managing to force that knot into Billy's muzzle, before he came with a something akin to a roar, pent up horniness forcing endless jets of cum to travel down the cub's throat.
They both moaned in unison as they rode out their respective orgasms, Billy the one to really see the moon and stars as he had been building this third orgasm up for a long time, his senses overwhelmed with strong foxcum, and the combined tastes of the many different kinds of shit he had ingested so far as well as the salty urine taste of just as many furs. All of these different tastes and sensations made his body wrack as if struck by lighting and he spurted cubcum again and again and again, even pushing out numerous jets after his daddy has stopped coming and just rested his cock down his son's throat, feeling it constrict and contract with every convulsion of his cubdick.
Brian enjoyed the feeling and looked down lovingly at his little shitslut, covered in brown and yellow and draped in toilet paper like some kind of B-flick mummy, the foxcub's eyes shut tight and an expression of pure extacy on his face, and he felt his dick harden up again from the continued constrictions of that tight throat and that delicous and naughty and filthy sight.
"Billy," he said, "I think I might be able to go for another round!"