Kara was usually a pretty light sleeper. Most nights it took only a slight nudge or a whisper to get him to lift his head and look around, and it was for this reason that the other person occupying the bed in which he was sleeping was a little giddy about what he wanted to try… There was no reason that the cat had waited for Kara to sleep other than he wanted to see if he could get away with it! The larger vulpine he had in his sights had the quilt only half-strewn over him, and as such his poorly-concealed, simply massive package was all but entirely exposed, the flaccid foot-wide dick flopped in the direction of Acer.
He didn’t know if he could take it much longer! God, the thing was even /drooling/, the leathery white foreskin pulled back just far enough that it exposed the fat black dickhead that it encased, which glistened in the dim light of the room. And there laid its owner, face less-than-attractively smushed into a pillow, completely out for the count. Or at least, Acer hoped he was out for the count. His paw reached towards it, heart beating faster for a reason he couldn’t quite fathom. There was something about this particular moment; he had his friend’s monstrous penis in sight, and he was on the brink of being able to do whatever he liked to it without Kara ever knowing. The thought tented the sheets between his own legs.
Finally, in the darkened room he felt his paw pads make contact with the slippery-slick cockhead. His eyes flicked over Kara’s face, checking for some sign of a reaction, but seeing no movement from him other than another regular exhalation. Encouraged, his paw slid down and was soon joined by the second, smearing the incessantly drooling pre-spunk all over that meaty, hooded glans, managing to tug the foreskin this way and that with each movement. Still Kara did not wake, though he stirred slightly, rolling a little more onto his back and spreading his legs before becoming still once again.
Acer was gradually building confidence. With his eyes intermittently returning to his friend’s face to make sure that he wasn’t being disturbed he slid down the bed by a couple of feet, greeting the several-foot dick a little more intimately… He hefted its absurd weight away from the bed and slipped a paw underneath it, finding even the underside of the head to be nicely slicked up.  The cat squeezed it firmly against his chest, drawing his tongue out to drag it around where the peak of the foreskin met the head underneath it, very nearly squeaking out in his unwarranted surprise as he found the soft schlong extending and bloating in his grip! The next sound to pierce the air was a moan from said endowment’s benefactor, now laying sprawled on his back, still drooling into the pillow as he was gradually given a massive erection by his friend. Whatever he was dreaming about, he was having fun.
“Really? All it takes to keep you asleep is a cockrub?” Muttered the intrepid cat quietly as he shoved his snout up against the head a little more firmly. It was steadily advancing, the entire shaft losing its floppiness and  being pushed into a far more rigid, definite shape. It was getting decisively heavier, too, and with a delicate slide of his fingers along the veiny, bloated underside, Acer found himself being bluntly smacked in the face with several pounds of force, the hardening meat flexing suddenly. Kara stirred far more definitely now, stretching his legs out and putting his paws up behind his head, grinning a dumb grin as he enjoyed his dream… Acer was having a hard time keeping his paws off himself, now, taking the occasional moment to stroke himself off whilst he touched and teased that ridiculous shaft into being so hard that it was standing up in the air by itself, bobbing a foot or so above its owners face!
For the first time, Acer dared to move his entire body. Kara looked completely out of it, tongue hanging out and eyes twitching away under their lids, and so the feline moved with a little more confidence than he would have otherwise, kneeling up to straddle that tower of penis, slowly working over it, clutching it between his thighs and slowly drawing it up against his body as he stood his feet to either side of his friend. The head of it had stretched so far away from Kara’s crotch that it was now pulsing directly in front of the cat’s face, fat as all fuck, the smaller fur’s barbed dick twitching against the mid-shaft as he slid the hefty white fox foreskin down with utter ease and locked it behind the head.
“Ooookay… You are going up me tonight.” He stated, more in the direction of the behemoth before him than the fox it happened to be attached to. He wasn’t kidding, either. He slid forwards and tucked the girth between his legs, continuing to sidle towards the head of the bed until he managed to slide the exposed head up under his tail… And then simply sat down.
Now, Acer was not a well-built creature. He was well-defined, but he looked similar to what would generally be called a twink, at least in his frame. And as such, as his elastic anal ring gradually spread around the positively ginormous insertion he was feeding into it, his hips could be observed widening to accommodate. He sucked down that foot-wide cock like it was nothing, though, gyrating his backside and gasping out as the head finally popped in past the outer ring of his rump. He had passed the first hurdle with flying colours, and the rest was easy. After that bulbous glans had vanished up his ass he only had to let gravity do the rest, gliiiding down the pole of pulsing meat and watching as his torso bulged out.
It’s important to note that, after enough time spent around Kara, the cat had been slightly corrupted on the inside. So as what looked to be nearly six feet of dick slid up his greedy, slippery anus, his body had very little trouble accommodating it. When Acer first sat down he watched his belly jut out in front of him, in the shape of the stonking great living dildo he’d found himself, before he sat up again, repositioned himself, and lowered himself slowly to savour the sensation of it forcing up out of his throat and into his mouth, soon completely impaled on the length of it! His face stretched absurdly and he allowed himself to enjoy his position for a moment, squirming his entire body to make Kara squirm. Not that the fox needed any more encouragement; he was already groaning out senseless noises in his sleep, dreaming vividly of doing something disgustingly lewd to someone. 
As Acer pulled back up he found himself getting slightly wedged. “Mmnphf…” He groaned, pushing especially hard against the cockhead which seemed to have managed to lodge itself outside of his face, finding no purchase… Before finally adjusting his jaw and allowing it to slip back down his throat. “Can’t imagine what it’d be like to have one of those jutting out of my face all the time…”
By now, Kara’s groin was producing vast amounts of fluid. Every drop was poured right into Acer’s willing body, the majority of it soaking right into the cat’s innards somehow. It was silently changing him, mutating cells and preparing his body. And thus, as the cat fucked himself silly on the inexplicably still-sleeping Kara’s hyper schlong he found himself increasingly driven to grind himself right down on the base of it, moaning out in delight, the bulge of Kara’s cock seeming to lessen… And finally after a good couple of minutes, Acer found himself slowing to a halt. Not deliberately, he just… Couldn’t quite move. 
“Huh… More lube?” He muttered to himself, really trying to stand up off the bed, but finding himself only pulling Kara away from the sheets! Making things worse, the bulge of the bigger fur’s dick was looking especially receded now, just leaving Acer with an expanded belly and chest which felt firm to the touch. “What’s… Why can’t I… Kara?” He spoke out loudly, now forgetting his quest to keep his friend asleep. The definition of his backside was starting to dwindle now, and he could feel his body shifting and reshaping against his will. “Kara! KARA!” He cried, his legs beginning to sink against the hyperfur’s hips as he sat in his kneeling position. They were simply melting away. This sincerely alarmed him, and he began to beat firmly on Kara’s chest. “Wake UP! WAKE UP!”
Kara, who had been having the time of his life in his dreams, finally stirred and shifted, reaching down for his cock as he did every time he was woken up. Except this time something didn’t fit right. He felt himself gripping his friend’s hips, but he could definitely feel that he was holding his dick. He grabbed again, this time taking a big pawful of Acer’s disappearing ass, his cock having completely melted into his insides. “What the fuck… Acer, what are you… Did you play with me in my sleep? Oh, shit!” He yelped and rolled onto his side, taking the cat with him and inadvertently thumping his entire weight into the mattress, his entire lower body having rounded off and become a definite dick-shape. Acer was squirming, trying to keep his arms away from his side, though they were melting into his body from the shoulders down…
“N-no… Okay, yes! Mm…Mnmnn… Help… Can’t be this… Bblrbl…” He was cut off as a thick wad of spunk pushed up out of his throat and dribbled down his chin, his neck starting to bulge out, rendering him completely silent.
“Augh, this is why I insist on quickies half the time! I can’t stop this, now!” He panted and huffed, doing his utmost to look pained and disappointed, but finding his hormones getting the better of him. He watched as the fur over the whole of his feline friend’s body receded, finding it impossible not to grind into the sheets at least a little. “Ah fuck, Acer… I’ll take good care of you…” He moans out, finally giving in and rolling onto his front where he promptly begins grinding fiercely into the cat’s mattress.
Down below, Acer was barely recognizable. Something absolutely massive was pushing out of his throat and face, his whole lower body having been recycled as extra ball mass for the already massively-balled fur. He was stretching longer and fatter, the yellow-skinned dick giving Kara one last desperate, hopeful look before his facial features were completely warped out of shape. A massive, pink cockhead slithered into his mouth, teeth dissolving, any remaining bones being reduced to simple flesh as what had once been a pretty, sightly face was reduced to a wrinkled foreskin. Something about the whole process made Kara moan more; watching his friend be utterly wrought of his features and mutated roughly into a penis even bigger, and ESPECIALLY fatter, than the one he normally had. He grabbed what was left of Acer’s face, that beautiful, luscious foreskin, and dragged it down the pulsing, barbed head, one that represented the one the cat had had before being… A penis.
That was all it took. Kara’s body quaked, the finality of having claimed his friend spurring him towards a massive orgasm which nearly knocked him out. He clutched his newly gigantic dick, balls pulling tight to his body, before dumping colossal amounts of spunk through his cat-dick with such force that he couldn’t quite find a noise to sum up the sheer orgasmic bliss racing through him. Amidst all the clouded screaming that was going on in his head, he decided on a sound after about ten seconds. And so after writhing and convulsing on the bed for what felt like an age, three households down the road would have heard someone howl out ‘FFFFFFFFFFFUUUUUUUUUUUUUUUUUUUUUUUHHHCK!’, that sheer geyser of jizz cascading all up the wall ahead of him, splashing into the ceiling and raining back down on top of him.
The next minute or so took forever, but finally Kara found himself able to stop tensing up, watching his brand new penis burble out the last few gallons or so of his orgasm. He was absolutely exhausted, clutching his softening friend in his arms and smooching the head,letting Acer’s changed face swallow up his cockhead again. “Mmmmph… Goodnight, pretty…”
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The next few days were awkward ones. Kara had the unenviable task of explaining away the disappearance of his friend, and all the screaming, AND all the volumous amounts of cum… All the while having to deal with the odd gawks from people in the direction of his HUGE dick, which had vague cheetah patterns on it, dragged behind him everywhere he went. It wasn’t entirely easy.
But hey, he got to sleep with his friend every night.