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It had all started with one stupid argument. “I bet you don't even know how to use your powers,” Karkat had said after hearing Dave brag about how much cooler Space was than Blood. “If they’re so great then show me.”
If he was honest, Dave had never actually tried to use his powers yet. He hadn’t needed to, anyway. He'd only said all that stuff to get a rise out of the troll. But he'd be damned if he was gonna back down now- he was tits deep in this shit now, and his ego wouldn't allow it. “Fine,” he retorted, his uncertainty well masked, “pick something and I'll show you.”
At first Karkat didn't know what he meant, but Dave just demanded again that he pick something. Anything. The two of them were sitting in the kitchen (or nutritional block, whatever the fuck trolls called things), so on a whim Karkat pointed to a jar of cookies sitting on the countertop. “One of those,” he told Dave dully, starting to feel unsure of his own bluff now. “Something small, in case you fuck it up.”
Dave rolled his eyes behind his shades, but he was secretly glad that it was something small. Hopefully something easy. Surely he could enlarge a cookie, right? How hard could it be? He got up and plucked one the pastries from the jar, holding it up and inspecting it. Okay, he thought. Now what.
“Well?” Karkat pressed, crossing his arms over his chest and smirking.
“Shut up, this is some elaborate shit happenin’ here, man. Let a dude focus.” And he was focusing, imagining the cookie growing in his hand as if that alone would make it happen. But there was nothing. Feeling frustrated, he tried again with an expression of somebody trying to see if they could use The Force to get the remote across the room. This time it began to spark and glow green. “See?” he exclaimed, only for his pride to quickly deflate when the cookie remained the same size, even after the glow had ebbed.
“I knew it,” Karkat chuckled a bit mockingly.
“I'm just not feelin’ it right now,” Dave replied nonchalantly with a shrug, then raised the cookie to his lips. "Even masters have off days."
“What are you doing?” Karkat burst out, taking Dave by surprise. The human paused, the dessert barely two inches from his lips, an eyebrow raised impatiently. “Don't eat that thing! It could be irradiated or some shit. Who knows what weird God Tier fuckery you did to it?”
“Seriously? I'm not gonna let a perfectly good cookie go to waste, dude. Trust me, it's totally safe.” Right? "Who's the Space player here?"
“But you-” Before he could finish, Dave had stuffed the morsel into his mouth, giving Karkat the double bird as he did so just to further spite his fussing and nagging. “Fine, assclown, don't say I didn't warn you.” Then, with an irritated huff, he spun on his heel and stomped away.
A few hours past without incident. Long enough for Dave to have forgotten the exchange altogether, and long enough for the hexed cookie to begin digesting. He’d just been sitting, doodling and rapping half-assedly to himself, as Striders were wont to do. Then, he began feeling… strange. He felt heavy and bloated, like he'd eaten a meal big enough for three. He figured it must’ve just been a side-effect from the weird cookie, and while he wasn’t entirely wrong, he never expected it to go so far.
He didn’t get truly concerned until he felt a light pressing sensation against his stomach, finally turning his attention away from his scribbles. What he saw made him nearly choke. His stomach, once flat and skinny, had bulged out to the size of a basketball. The pressure he felt was the table pressing into the soft, doughy flesh beneath his black costume. And it was getting bigger. Slowly but surely, with a low gurgling now, the newfound fat of his gut was expanding.
“Oh my god,” he grunted in dismay, gripping the sides of his suddenly fat gut and giving it a frantic, experimental shake, as if to be sure this was really happening. It jiggled and bounced in his grip, black fabric riding up just slightly to expose the flesh underneath. This was really happening. “Fuck, fuck, fuck…” Squishing his stomach, he began silently, desperately begging it to shrink back to its normal size, trying to employ his Space powers.
As if to spite him, his body began growing… elsewhere. Everywhere, actually. The first thing he noticed was his thighs, widening and spreading until they not only touched each other, but began to feel squeezed by the arms of the chair. Worse yet, he could feel it in his ass too. He dared a timid look over his shoulder, only to be met with the sight of his backside swelling, filling up the chair like an overinflated balloon.
His clothes felt tight all over. Sure, the fabric was decently loose and pretty stretchy, but nothing could withstand this. He could feel the seams audibly groaning against his billowing mass, stretching and straining to their limit. The chair was holding up no better, sinking under his increasing weight while the arms hugged his thunderous hips tighter and tighter. Rolls of flesh began spilling out over the edge of the seat, his stomach now so big that it spilled into his lap and began pushing the table away from him until finally knocking it over altogether.
He opened his mouth to yell for help, only to suck the air back in. No. No fucking way in goddamn hell was he gonna beg for someone to save him. Fuck, if Karkat found him like this, he’d never hear the end of it. Not only for being exposed as not knowing how to use his powers, but also for just... this. Swelling up to a massive size, growing fatter and fatter all because of his own unruly powers? No. Totally uncool. Dave decided that he’d gotten himself into this mess, and he could get himself out. Besides, he thought with some relief, the growth seemed to be slowing. Again he held his belly, lifting it up and wincing at how heavy it was in his hands. He noted that his wrists were thicker, his once defined knuckles round and soft. Even his arms had more than doubled in size, and his face felt round and heavy; there was no longer space between his jawline and neck, a pronounced double-chin having replaced it.
This was fine. He could fix this.
Running his hands everywhere he could reach (which wasn’t much by that point) he concentrated on himself shrinking back to his original size. At first he thought for sure it was working, if not sheerly due to dumb hope, only to be dismayed as the chair gave one final shriek of protest before shattering under his bulk. His ass his the ground with a massive thud , every roll of skin rippling and wobbling from the force. Then he was growing again, maybe even quicker than before. Now he could feel his skin expand, taking up more and more space as it filled out his clothes and spilled against the floor. By that point his shirt had been pushed up to his blossoming boobs, the seams at the sides starting to split as he continued to get bigger. And bigger. And bigger...
“Shrink, shrink, shrink,” he begged softly, his breath beginning to heave with the effort of… well, everything. But every plead he was met with a defiant sound of rending fabric, starting with the quiet stretch and tear of stitches, followed by full-blow shredding. He could feel it in his pants at first, the sides tearing apart with loud rips that practically echoed in the quiet room. His hands flew to where he felt the little bit of relief, barely able to even reach his thigh to feel the way his flesh squeezed out of the holes it had made, only to stretch said holes further. Riiiip. The seat of his pants went next, shredding around his loveseat-sized ass.
“Dave?” His rampant heart seized up for a minute when he heard that voice. Karkat’s voice. Deep down he knew it was all over, but he remained quiet as if the troll might give up and move along. “Dave, what the fuck's with all the noise? I know you're still in here.”
Guess it was time for him to just keel over and die, and save himself the humiliation. He didn’t have time to tell Karkat to leave, even if that would’ve worked. As the troll turned the corner, his eyes widened to globes as he took in the scene. Splintered wood disappearing under a quickly expanding mass of flesh, the table knocked over by a belly bigger as he was, black fabric ripping apart to reveal pale, abundant rolls of skin. And on top of it all, Dave. Wait, no. Not on top. It was Dave. All of it.
At first Karkat was frozen, confusion and slight horror apparent on his face. However, he was less horrified by what he saw than by the way it sent blood rushing to his nether regions. Dave was massive, and growing fatter by the second. His expression was pricelessly pitiful too. His round cheeks were red as could be, his lips quivering, twisted into an unspoken plea, and his eyebrows pinched with humiliation. Karkat smirked, stepping closer and putting his hands on his hips.
“I warned you,” he purred lowly, reaching out to grab a handful of the love handles that spilled out over the last remaining threads of black fabric.
“Sh-shut up,” Dave gasped out, unable to reach far enough to smack Karkat away. The touch had felt undeniably, sinfully good though. If he was honest, he’d been hard for a while, but his cock was stuck between the huge, lower fold of his stomach and the cold concrete floor. He’d been too afraid and embarrassed to really notice it before, and even if he had there was nothing he could do about it. But now, with that taunting touch, he felt it. And it ached . He knew this should not be turning him on, and that arrogant, taunting look on Karkat's face should not have been so erotic... but it was.
“Well, you sure showed me,” Karkat mocked further, shaking the handful of expanding flesh and watching mesmerized as it sent ripples through the rest of Dave’s body. "This is too good. You're so fucking fat, Dave." His voice was condescending and scornful, making Dave writhe with both arousal and humiliation.
Dave squirmed, the futile motion leaving him a little breathless, and not just because of the way his belly squashed and molded around his rock-hard member. He was huge. “J-just shut up and help me!” he finally pleaded, his pride officially shattered. As if it hadn’t been ages ago.
“What am I supposed to do?” Karkat asked a bit incredulously, circling Dave and scanning, memorizing every detail. The human's pudgy arms were dwarfed by his humongous gut, able to do little more than rest atop the soft mound. His legs were forcefully spread apart by their own width, each probably as wide as Dave’s whole body had been less than twenty minutes ago. The part that had suffered the most though was his rear, his body now having an exaggerated pear-shape.
“I-I don’t know!” Dave flustered, futilely trying to turn his head and watch as Karkat inspected him. The sheer mass and padding made him a good bit taller than the troll, even while sitting. “Just stop being a smug son of a bitch and do something!”
“Can you stand?” Karkat asked curiously, but he knew the answer.
“Does it look like I can stand, asshole?”
Another low, spiteful purr erupted in Karkat’s throat. “I guess not. I’m not even sure I’m strong enough to roll you out of here.” The mere thought of it made both of their members throb. “Not that you’d fit through any doorways like this. You’re big, fat ass would get stuck, for sure.”
“Nngh, Karkat,” Dave whined desperately, blushing all the way down his neck. “Knock it off already.” His fists clenched meekly against his gut, the human panting softly. “Y-you’re having… way to much fun with this, you jerk...”
“Fine, you want me to do something?” Karkat taunted, now standing in front of Dave again. “I’ll do something alright.” Then, relishing the way his hands, even a good third of his arms, sank into the fluffy, pillowy fat, he lifted the fold of Dave’s stomach up, ready to let it slam back on the ground to create a brand new shockwave through pudgy flesh.
Then his situation became a little clearer. Karkat could barely see it, but the shift of Dave’s fat stomach showed the precum-oozing tip of Dave’s dick. His following, sharp-toothed grin was scathing.“And you said I’m having too much fun,” Karkat snickered, having to hold the heavy roll up with one hand just to give the member a stroke with the other. Dave shuddered, sending waves through his abundant flesh, and Karkat found himself shivering too.
“You’re-” Dave groaned, his tree trunk-sized legs and enormous hips squirming with no small amount of effort. “You’re fucking sick.”
“I guess that makes two of us.” Quicker than Dave would’ve liked, Karkat had let his overhand drop with a dull thwap against the floor. The blonde winced, choking down an erotic groan. Then, faster than Dave could protest, Karkat had begun to climb on top of him, grunting a bit with effort. Dave's skin was so abundant and malleable, it was a bit hard to get a good foothold. But he managed. After a few moments of squishing, pulling and prodding, Karkat sat himself atop the roundest part of Dave's stomach, either hand gripping a fistful of moob. “Wow,” the troll hummed, fascinated by how he sank into Dave’s ocean of a gut, how his breasts squashed and spilled out between his fingers. “You’re like a… what are they called? Those big sleeping pads you human use, except filled with water.”
Dave groaned in a way that neither one could tell whether it was embarrassed, annoyed, or lustful. He didn’t dignify Karkat with an answer, but all the attention, the touching and the mocking words were affecting him in a way he didn’t want to own up to. “Fucker,” he whined, the bite to his word subtly softened by the confusing mix of emotions flooding his brain.
“Fatass,” Karkat retorted without hesitation, and the word made Dave keen a little with want, only for him to snap his mouth shut again, mortified by his own vocalization. “Wooooow,” Karkat practically giggled, if that was even a thing the moody little troll was capable of. “You really are getting off on this, aren’t you?”
Dave thought that perhaps he would be if he was capable of as much, humiliating and weird as it was. Then Karkat surprised him by reaching up to cup the folds of his double-chin. Then, he began doing something that made the human’s breath hitch in a tiny, pleasured gasp: he started grinding his hips into his stomach, the rocking motion making his whole body wobble.
There was even enough motion to give his member a bit of much-needed friction underneath his spilling muffin top. “Oh, ffffffffuck~,” he whimpered, watching Karkat straight up dry-hump his massive gut, the troll grinning all the while. “Fuck, Karkat-”
“That’s what I’m doing,” the troll replied dryly, licking his lips as he started moving faster. He started to hum and moan himself, the friction sending heat and tingly, lightning-bolt pleasure throughout his core. “Nng, Dave-... you’re so fucking massive…” he sighed, his head tilting a bit as he watched Dave’s expression twist with suppressed pleasure and his body jiggle like a gigantic bowl of jello.
Hearing him say that with such lust, maybe even affection, made Dave melt. He appeared to have stopped growing, so with that panic gone he was able to… well. He supposed he was enjoying this? As weird and sick as it probably was, he couldn’t deny that it was just as hot. His hands flexed helplessly at his sides, and he didn’t even have the strength to grind his hips, not that it would’ve done much good.
“You like that?” Karkat guessed, shifting so his face was half-buried in Dave’s blubbery chest. He could barely see the troll’s bright, yellow, hooded eyes as he gazed up at him with want. “You like when I talk about how fucking fat you are?” Then he opened his mouth, and Dave thought surely he wouldn’t-
He did. Using one hand, he shifted a fat layer of Dave’s chest around until he managed to find his nipple, biting and sucking, purring as he mouthed the yielding flesh. Dave could hardly breathe, let alone answer Karkat’s previous question. So he just nodded his head vigorously, lips quivering and red cheeks wobbling. Karkat’s mouth separated from his watermelon-sized breast with a pop, the troll licking the dark ring of his nipple teasingly.
“Nng,” Karkat grunted in pleasure, bucking his hips harder and harder. “God, fuck, you’re so big…” He was panting now, his own expression turning weak and melted with lust, his cheeks burning just as brightly as the human’s. “I-I’m gonna come!”
As if those words had been the trigger, the troll cried out as he climaxed, hugging Dave’s gigantic belly with his whole body as he rode the orgasm out. Even Dave felt close, the movements of his body around his cock providing ample friction. As if he could tell this (and he probably could, based on Dave’s breathy moaning alone) Karkat kept ramming his hips into the blonde’s fat rolls until his head rolled backwards, and a shaky moan bubbled up from his throat.
As the two came down from their mutual high, the ecstacy ebbing, the full weight of what they’d just done began to settle on them. Karkat sank into Dave’s breasts and his gut, catching his breath as he let the warm plushness overtake him. Dave, by some miracle, managed to move one thick arm to wrap halfway around the troll. “So,” he stuttered out a bit numbly, his mouth dry. “That was… a thing.”
“A fucking amazing thing, thank you very much,” Karkat corrected, giving either of Dave’s moobs a squeeze, or at least as much of them as he could fit in his small hands. “Don’t even act like you weren’t insanely into that.”
Dave grunted in response, heaving a sigh as he scanned over as much of his hugely bloated body as he could see. Karkat had been right about one thing: even if he did manage to roll him out of the kitchen, there was no way he’d fit into any of the rooms. He was too wide. Too round. Too fat. He tried not to think about what would happen if he was stuck like this, because that wouldn’t happen. Right? He could definitely totally fix this… somehow. Eventually.
“Eventually” had turned out to be the next morning. Amazingly nobody had wandered into the kitchen in the dead of night, but if they had they would’ve found that the two had, at some point, dozed off in that same position: Karkat perched atop a hill of fat, Dave’s arm barely reaching the troll’s waist. By the time they woke up, however, they were sprawled on the floor, tangled in each other’s limbs.
Dave was totally naked, but that was to be expected. He’d torn through every inch of his god tier outfit, after all. The floor was cold on his back, but a warm body filled his arms. As he opened his eyes, his shades askew, he realized that he no longer felt heavy and bloated, and he was no longer immobilized by his own mass. Also that he and Karkat were just cuddling on the floor like that was a normal thing to do.
He managed to shake the troll awake, if not just so he could sit up and inspect his body. He wasn’t skinny by any means, not like he had been before. But at least he was back down to a manageable size. His stomach still hung over his lap, his sides bunching into love handles, and his ass round and plush. Honestly he was just happy he could stand on his own again.
“Guess that space magic isn’t permanent,” he mumbled with a mixture of relief and embarrassment, making no effort to hide his shame. After all, he and Karkat had more or less fucked the night before, so what did it matter?
“Good,” Karkat purred, reaching his arms up and around Dave’s neck. “That means we can do that again. And again,” he kissed the underside of Dave’s only-slightly-chubby chin. “ And again. ”
“You sick fuck,” Dave chuckled, his tone half salty and half sweet.
“If I’m a sick fuck then you’re a fat fuck.”
“Damn straight.”