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Dave is browsing a fake floppy dick shop on the internet. Karkat insists it’s called a “concupiscent enhancement device shop.” Maybe the truth is somewhere between the two. He’s so glad he decided to do this online, because just looking at this shit makes him blush. Dicks and balls in every shape and size and several materials he’s never even heard of. He keeps checking over his shoulder to make sure that no one is watching him, even though Karkat is out and makes a hell of a lot of noise just by default, so there’s basically no way he could have missed him coming home. And even beyond that, there’s basically no way that Karkat would sneak up on him, even if somehow he had. But still, a guy needs his privacy to browse fake floppy dicks on the internet.
The thing is. He and Karkat have tried to do ass fucking before. And they even did it, before Karkat hit his insane growth spurt about a year after they started dancing the horizontal tango. And it was great. And then Karkat had an extremely grumpy, painful few months and came out on the other side a foot taller and considerably more well endowed. Like, considerably. Like, the thing couldn’t get even halfway in before it felt like it was going to rip Dave in half, and not in a sexy way. One time he tried to just push past the alarm bells in his head and get the thing inside. He bled and it hurt to sit for a week. Never again.
Karkat’s fingers are nice. He keeps his claws clipped to nubs so that he can use them with Dave, stick ‘em up there right where they need to go. But Dave has always kind of missed it from before. It was really fun, in an overwhelming way, right off the bat, to have Karkat’s bulge whipping around inside of him. And it was so hot when Karkat would come in him, fill him up even further with an excessive amount of jizz. Well, that part he can probably never get back, but the other part, the being filled and overwhelmed, maybe. So he’s looking at fake floppy dicks.
Maybe he could have Karkat use one on him. Maybe that wouldn’t make him sad. Hopefully. Hm. Need to broach the subject carefully, gather data before popping the Q. Dave knows that Karkat is kind of bummed about having a dick bigger than a baby’s arm. No one asked him if he wanted a debilitatingly huge monster of a goo gun. He keeps the gigaschlong jokes to a minimum, because it’s kind of a sore subject.
He eventually finds one that doesn’t make him too nervous about the fit. The checkout asks him if he wants lube. He says no, then pauses.
See, Karkat makes his own lube. Kind of. He produces enough slick pre-come genetic material that he can wrap his tentadick around Dave’s humadick and have it nice and wet instead of gratingly dry. But it’s not nearly enough to do anything in the backdoor region, besides just little sorts of rimjob type things. Which are great. Which are super great, absolutely no complaining about those. Dave is basically always down to clown with those. But, lube. Lube, he’ll need that for this dildo. But lube, more importantly, he realizes, is what he might have always needed for Karkat. It just wasn’t available during the game. The internet was nonexistent, and even if he or Karkat had thought of using the alchemiter to make some (they hadn’t), they would’ve had to just keep throwing shit in and guessing, which was pretty heavily frowned upon given the whole limited resources thing, and the stake of the universe and shit. No longer a concern. Universe is secured. Lube is an option.
Holy shit, though. Maybe Karkat can actually fuck him now. Maybe Dave doesn’t have to settle for this sparkly pink glitter 6 inch with balls that are just a little too veiny (which is hilarious, yes, more of that). He puts the dildo in the cart just in case, but he throws in two different kinds of lube, too. He gets express shipping because he’s a fucking god and he can. Shit, maybe he could get a saved the universe discount. He decides against trying, because a) that might be going against the agreement that he and the rest of his friends had lined out to not fuck with the local economies, and b) that would confirm to the fine purveyors of this upstart establishment that, yes, this order of dicks and lube was, in fact, for that Dave Strider.
So, he checks out, pays the amount on the screen, and waits. He waits and waits until it arrives. And then he unwraps the package. Sets the lube on the table next to the bed, wrestles with the packaging around the dildo and washes the thing off. And then he goes to find Karkat.
“What the hell are you smirking about? You’re creeping me out.”
“Got something fun in the mail. Something real fun.”
“What kind of ‘real fun?’ Like pizza? Or like, a new game? Give me a hint here.”
“Dude, did you have pizza by mail in Alternia? That’s genius.”
“Yeah, didn’t you? Were you just expected to make your own pizzas?”
“No, man, someone else made it and then drove it to your house.”
“That sounds exactly like what I just said. Where is the difference between that and what I just said?”
“It’s lube,” he blurts out. Shit. This was some good banter they had going.
“The difference is lube?! Did you put lube on your pizza? Did-”
“No. I got lube.”
Karkat’s mouth opens, then closes. “Good… for you? I mean. That’s hot? Good for you, seriously, but I don’t need to- we don’t use-”
“Think about it.”
Karkat’s eyes narrow a little. He looks suspicious. Nope, not yet.
“Think about it harder.”
“What the fuck-“
“Harder than that, even.”
And then his eyes go wide, and his cheeks flush bright red.
“There we go. Are you down?”
“Why didn’t we think of that sooner?”
“Beats me, dude. We did have a lot of other shit to think about.”
“Fuck. Okay. Yeah, good. Okay.” Karkat is so flustered, it’s really cute.
“You okay?”
“When’s it getting here?”
“Oh, it’s here.”
“Oh. Fuck. Shit. Okay. Do you want to, like, now?”
“Sure do.”
*
As soon as they get to the bedroom, Karkat very helpfully rips Dave’s clothes off for him. He doesn’t tear them, which is good. Right after the growth spurt, he tore a lot of them, all this new strength he didn’t know what to do with, but he’s figured it out in the years since them. Dave pulls Karkat’s pants down and gets on his knees and helpfully kisses at his nook. Karkat’s hips really buffed out after the puberty thing, probably so that they could store such his gigabulge in there, and Dave loves getting his hands on them basically whenever he can.
“At least get on the bed fir- what the fuck is that?”
Dave pulls away and licks his lip. “You found the dick?”
“I didn’t ‘find’ it, you put it on the desk.”
Dave doesn’t need to say anything to that. No he doesn’t. Karkat is just stating the obvious, which he does sometimes, when he’s feeling vulnerable. Like when he’s stark naked with Dave between his legs. Dave starts licking at him again.
“Fuck. Fuck, Dave…” He sounds so good. Dave knows they have other plans, but honestly he could just do this for hours, and wants to do it until Karkat pulls him off. “Do you wanna start with that?” he asks, his voice tighter than before.
Oh. Dave nods and pulls away for just a second. I’ll be back, sweet prince. “Shit, you’re a genius, yes?” Absolutely, yes. Why hadn’t Dave thought of that? It’d get him nice and open for business.
Dave tries to get his tongue back up in there, but Karkat pulls him up before he has a chance. Dave’s stomach does a little flip when Karkat just picks him up like he’s a carton of eggs and sets him down on the bed. He’s so ridiculously strong, it always makes his heart race. And his dick swell. It really ought to be more alarming than it is, but it’s just hot.
Karkat spreads Dave’s legs with his big hands, and Dave’s heart hammers in his chest. Time hasn’t done much for making this feel any less vulnerable or open. Like, hey, here it is, my dick and ass, open for your particular business, just out there in the breeze.
Karkat peels the wrapper off of the lid, pops it open, and tries to put some on his hands. And tries again. He tries jerking the bottle forward violently, like he can force the goo out by sheer force of will.
“Having trouble?”
“Fuck off, it’s stuck.”
“Let me see it.”
Karkat tries squeezing the bottle again, then tosses it to Dave. Dave tries to squeeze it, to no avail.
“Weird.”
“I was just doing that.”
“I know, uh.” Dave tries shaking it out. Maybe Karkat had the right idea there. Oh, wait. No. He unscrews the lid and, yeah, finds another seal underneath it. He peels it off and dumps the bottle upside down, just to make sure, and a giant glob of lube lands on his thigh.
“Got it.” He winks and gives Karkat fingerguns.
“Yeah, all over your leg.”
“Yeah. That’s a problem. Uh, let me…” He goes ahead and shifts the lube over from his leg to where it needs to go. They’re wasting enough time, and Dave is starting to flag, and he’d really appreciate if they got this show on the road.
Karkat kisses at the inside of his leg and the flagging is gone. He feels his a thick finger pressing up against him and gasps. Flagging is totally gone, mood is totally back. And Karkat’s finger actually goes in, easily. Way easier than it does when they use Karkat’s homemade junk lube.
“Holy shit,” Karkat says as Dave gasps. Fuck, he just slides the entire finger right in. And he goes for a second one without much more resistance. Dave just takes it.
“Fuck. Fuck, this is the best idea ever, this is totally gonna work.”
Karkat pulls his fingers out and slowly pushes them back in.
“What the hell is this stuff? This is unbelievable.”
“Fucking feat of nature, right? Oh, fuck.” Karkat adds a third finger and, oh, okay, that’s a lot. Not too much, yet, but. “Slow down.”
“Oh, shit, sorry.”
“You’re fine, just, keep going at that pace and I’m li-i-i-“ Dave cuts off when Karkat pulls his fingers out. Fuck, it’s a lot.
“What were you saying?” He puts them back in, only two of them this time.
“What the fuck was I saying? I don’t know. Good shit.” Dave picks up the lube and squirts more down there.
“What are you doing?”
“Try three again now.”
He does. It’s. Good. It works this time. His fingers, all together, are wet and slick. Karkat can actually fuck him with his fingers now, as opposed to the normal thing, which is more just, rubbing at Dave’s prostate and keeping the friction low so it doesn’t get too painful. Which is great in its own way. But this is a lot. This is different. He’s actually getting fucked again.
“Are you okay?” Karkat asks.
“So fucking okay.” Dave feels fluid drip from his cock onto his stomach. “Holy shit.”
“Fuck. Do you want to… you know?”
“Yeah, fuck yeah, do it.” Dave tosses the dildo in Karkat’s direction. He shivers when Karkat pulls his fingers out.
Karkat covers the thing in lube and then lines it up with Dave’s entrance. And he notes that Karkat’s other hand slips between his legs for a few seconds, and that he bites his lip and his eyes get glassy. Fuck, that’s hot. And then Karkat pushes the thing in.
“Holy shit.”
It’s overwhelming. In the past few years, Karkat has sometimes slipped just the tip of his junk in. All Dave is used to is that and the occasional finger down there, if anything. Even with all the prep, this is so much more. It’s huge and unyielding. He tries to clamp down around it and it doesn’t go anywhere.
“Are you okay?”
“It’s. Really thick.”
“Can I move it?”
“Slow.”
He moves it, slow, and Dave gasps.
“Fuck, it’s so fucking much.”
Honestly, as good as it feels, he feels kind of nervous, because this was supposed to be the warm up, and he can barely take it.
“Is it too much?“
“Listen, I’ll tell you when I’m not okay, I swear to god you can stop asking, it’s not- nn-“
“If you say so,” Karkat says. He pulls the thing out, sinks it back in so slowly that Dave feels every delicious bump and ridge on the thing. It’s so good. He shudders. “Are you sure? It’s been a really long time-“
“I swear to God, Karkat, I’m positive. Don’t stop.”
“Ar-“ Karkat clears his throat, as if that’d cover up the fact that he was about to ask again if Dave was sure. Honestly, it’s adorable and makes Dave feel all warm and fluffy. Ever since those few times when they’d gone a little too far, too fast, entered the bloody ass red zone, Karkat has been super hesitant to do anything that might conceivably hurt Dave. Honestly, Dave is pretty sure that event traumatized Karkat more than it traumatized him – he just had a kinda painful ass for a few days, but Karkat was still worried about it today. Well, hopefully lube starts to fix that issue.
“It’s so big. I don’t think you’re gonna. Fuck. You’re gonna be able to fit, today.”
If Karkat is disappointed, he doesn’t show it. “That’s fine,” he says. “Well, it’s not like we can’t do this for a few days to get you… ready.”
Dave gasps. Fuck. Fuck, that’s hot.
“Shit.”
“I think you’d want that.”
“No shit, absolutely.”
Karkat pushes the thing in again. Fuck. When Karkat fingers him, he crooks his fingers and rubs up against his prostate. That’s pretty impossible to do with this thing, it’s too big, it pushes right on past that little shiver bundle. Instead, it kind of drags alongside it just a little, unrelentingly, every time it moves. It sends little tingles all the way to the tips of Dave’s fingers.
Dave runs his hands through Karkat’s hair and rubs at the sensitive little crook where his horns meet his scalp. Karkat leans into it in a way that kind of reminds Dave of a friendly cat. His cheeks are flushed and his eyes have a foggy look to them. His bulge must be fucking whipping around down there. Dave thinks he can hear it slapping against itself, but that might be the dildo.
Fuck, he wants that inside of him. The longer they go at this, the more comfortable Dave gets with it, and the more he wants to see Karkat’s face when he finally sinks down on him, after all these years.
“Let’s try it today, though.”
Karkat swallows. He gives Dave a look. Are you sure? That seems like a bad idea.
“Actually, let’s try it now,” Dave says.
“What, like right now?”
“Yeah.”
Karkat swallows again, and pauses a moment to think about it. He’s a little bit slower on the draw than usual, probably because his dick is literally so big that he usually gets kind of dizzy when he’s raring to go. God. Honestly, Dave’s felt so bad for him over the last few years, the whole “giant dick” thing was way more pain than gain. “How about we do this longer?” Karkat asks. He pushes the dick in and kisses at Dave’s thigh. “Make sure you’re ready.”
“I can literally hear your dick slapping against itself down there.”
Karkat’s blush gets deeper. “So what?” he asks. “I’m fine, don’t worry about me.”
“But what if I want to?”
Karkat looks unconvinced.
“What if we go really, really slow?”
He looks a little less unconvinced.
“What if I ride you? What if I swear that I’ll stop the second it starts to hurt?”
He sees Karkat coming around to the idea. Karkat wears his heart on his sleeve, always has, and it’s super endearing. He watches that little bit of logic (and trust or whatever) push past the hesitation and sees his other head take over. He pulls Karkat up and sits him down on the bed, his back against the wall. Like Dave suspected, Karkat’s bulge is eagerly wiggling around under him.
“Fuck, it’s so big.” Dave wraps his hand around it – just barely, it’s too big to get a solid hold on – and starts to stroke him. Karkat’s eyebrows knit up in pleasure.
“Shut up,” he says, his voice strained.
“I’m so excited to take it, dude. Seriously.” Fuck. Dave’s not talking it up for Karkat’s benefit. Just looking at the thing, feeling the weight of it in his hand, huge and wet and undulating slowly in the open air like this, he can almost imagine what it’ll be like inside of him. “Fuck, dude, you’re gonna split me open. It’ll feel so good.”
“Dave, please.” He sounds like he’s on the edge of restraint, and his bulge slaps against him almost violently.
Well, that’s all Dave needs. He gives Karkat’s thick fucking bulge a few more strokes before he grabs the lube and gives it a good, thick coating. He spends more time than he absolutely needs to down there, because Karkat did him such a solid with the dildo and his junk needs some love, too. Then he gives himself another fresh coat of lube. “You can’t have too much lube” seemed to be the consensus on all the sites he’d been on, when he was amassing his data about how to best get fucked by monster dicks. And he gets up, straddles Karkat’s thighs, and lines up.
He had figured he’d have to do more work, but the second he sinks his hips down far enough, Karkat’s bulge presses up against him. It’s like it’s kissing him, or licking up all the lube that’s dripping down his thighs like his ass is a leaky faucet. And then he feels the tip start burrowing inside. Fuck.
“Slow, dude,” he says, and his voice sounds tight.
“I’m trying.”
And it pushes in. Slow enough. He’s biting his lip, and Dave can see that he’s concentrating on controlling his bulge as much as he can. Which isn’t a ton. The thing kind of has a mind of its own. Like how dicks get hard whether you want them to or not. Bulges thrash, and they seek out hot and warm and wet. But Karkat is keeping it slow for him.
The tip, Dave is used to. The first few inches, Dave is used to. And then it pushes a little farther. Dave gasps and Karkat swears under his breath. This is farther than they’ve ever gone before, and Dave can feel it. It’s thicker than the toy, but it has so much more give, and he feels like he can take more. A lot more. He bumps his forehead up against Karkat gently and kisses him.
“How’s it feel?” he asks.
“You’re so fucking tight, are you okay?”
Fuck. Whether this works or not, Dave is getting Karkat off so many times. Fuckin. Nice ass motherfucker, worrying about whether or not Dave is in pain first and foremost.
“I’m doing great. You can go deeper.”
“Are you… fuck,” he says as his bulge starts to undulate. Holy shit, that feels amazing. Dave cries out and his back arches. “Was that a good sound?” Karkat asks, frantic.
“Karkat. Yes. Please assume okay until I say I’m not, and do that again, please.”
He does it again, and Dave’s vision gets blurry. Honestly, Dave wasn’t thinking with his bigger brain when he proposed this. Karkat was right, they probably should have waited a few days, done this a bit more before diving in. But now he’s pretty sure this was the best idea he’s ever had, for real, he’s going to take the vast majority of Karkat’s monster dick and come from it. And Karkat’s face, god. He’s biting his lip hard, his eyebrows are drawn up tight, his eyes look like they can barely focus but they’re locked on Dave.
Dave leans over and kisses him again, and sinks down a little deeper. Karkat moans into his mouth and digs his nails into his hips. And then pushes him down even further, sending little shivers down Dave’s back.
Dave gets the idea. He starts rocking back and forth gently, feeling Karkat’s bulge slowly writhe inside of him. It’s hard to think about anything but how fucking full he feels. Fuck, and it isn’t even all the way in.
“Shit, yeah, that’s the stuff, it’s so good.”
Karkat swallows.
“I’m. Not gonna last.”
“Woah, seriously? It’s been like 30 seconds.”
“Shut. The fuck up. It’s been. So fucking long.”
Dave keeps rocking his hips. He leans over and listens to Karkat’s ragged breaths. “Can’t wait to take the whole thing all next time.”
Karkat’s nails dig into Dave’s hips sharp enough to sting and his bulge thrashes. That makes Dave buck his hips. Which makes Karkat’s bulge thrash more. It’s a feedback loop that rapidly spins out of control, and before Dave knows it he’s leveraging himself on the headboard and just trying to ride the thing, which is thrashing like a fucking bronco. He’s making all kinds of fucking noises that he can’t be assed to be embarrassed about because jesus Karkat is fucking huge and moaning and his bulge is fucking whipping around in there with the little fucking wiggle room it has.
And then Karkat pushes Dave’s hips down, making him sink down on his bulge another half inch that feels like it’s a fucking mile thick. Dave’s eyes fly wide open in shock as he feels Karkat actually expand in him, and he makes a helpless, pathetic little whimper as he feels him start to gush. Inside of him. Fuck. Fuck, it feels like there’s no room, but there is, somehow.
And then, like always, Karkat’s bulge slowly withdraws. This time, it withdraws out of him, giving him one last little (giant) thrust before shinking back into his body.
Karkat pulls him down and kisses him, still breathing heavy. He wraps his hand around Dave’s cock and starts stroking him, and Dave starts squirming in his lap. Fuck. He’s so fucking overwhelmed, and hard enough to cut fucking diamonds, and Karkat’s hands are so good and big and soft and it almost feels too good. It doesn’t take long for him to spill, dribbling spurt after spurt of come weakly onto Karkat’s stomach as the feeling wracks him for what feels like minutes.
They kiss for a while, until they can breathe normally again, and then roll over on their sides. Karkat’s genetic material is fucking everywhere, but they have waterproof bed linings, and like fuck is Dave going to be convinced to move for the next half hour, at least.
“You did it, dude. You fucked my butt.”
“I know. I was there.”
“Shit, you were. You totally were. How did I miss that? Fuck.”
Karkat snickers. “Shut up, oh my god.”
Dave burrows up against Karkat. He’s so big. It’s great. Big, warm, soft, sweaty, with a powerful heartbeat hammering so fast he can feel it through his skin as it slowly starts to even out. Just right.
They doze off for a while.
Dave’s ass starts to ache not too long after that.
“Yeah, shoulda gone slower than that,” he says sleepily.
“You okay?” Karkat asks tiredly. He sounds like he’s about to fall asleep.
“Mm.”
“Think my bulge is literally bruised.”
“No shit, really?”
“Mmhmm. Slower next time.”
“Hell yeah.”