Kyle threw down the game controller with vengeance and a cry of fury as the screen turned black and the words 'GAME OVER' appeared in big, blocky, taunting capital letters. "Motherfucker!" he screamed, crossing his arms and pouting, "Why can't I get past that fucking level?!"

Behind him Cartman laughed, and Kyle turned in his seat in the larger teenager's cross-legged lap to silence him with an angry look. "Dude," Cartman kept laughing, undeterred, and wiped a tear of laughter from his eye. "You fucking suck at Mario."

"Argh!" Kyle threw his hands up in the air in despair and snatched up his homework from the floor: the thing he was meant to have been working on before he had gotten distracted by Cartman's video-games. "Whatever," he huffed, "It's not like you could do any better!"

"Is that a bet, Kyle?" Cartman asked, picking up the abused controller and wrapping his arms around Kyle to hold it aloft in front of him.

"No, it's a fact." Kyle replied, angrily pressing pen to paper to scribble in the answers to the math equations.

"We'll see about that." Cartman smirked and restarted the level. The nostalgic cheery music started up again and Kyle could hear the sound effects of hopping and coin collecting but didn't look up to watch, too angry with the game to bear looking at it. He just leant back against Cartman's chest and relaxed in his boyfriend's lap, thankful that Cartman was as fat as he was, because it meant he made for a comfy chair.

Cartman rested his chin on the crown of Kyle's head, too invested in the game and proving Kyle wrong to be bothered about the way the red curls tickled his skin. While Cartman's thumbs flew over the buttons, Kyle's pen flew over the page, until he had answered all the questions with great certainty that they were right. He looked up at the screen to see how Cartman was doing, and he went slack-jawed when he was stunned to find that Cartman was actually doing pretty well and hadn't even died once.

"What the fuck, dude?!" Kyle exclaimed, unable to believe what he was seeing. He had struggled so hard to get even a quarter of the way through that level, and Cartman was already half-way through and making it look altogether far too easy.

"You're about to lose your bet, Kyle." Cartman replied confidently, "That's what the fuck is up."

Kyle ground his teeth together as he watched Cartman scoring high points, dodging all dangers, and kicking the asses of all the enemies, all without even breaking a sweat. Cartman did play video-games too much though, Kyle knew from the times Cartman had explained his lack of completed homework by telling everybody that he had been kicking ass in COD. The teachers never had liked that excuse very much.

"Hey, Kyle," Cartman said with a quirk of his lips, "When I win this bet, I get to copy your homework."

"No!" Kyle frowned, jabbing his elbow behind him, digging it sharply into Cartman's gut. "You won't learn anything if you just copy my homework!" It was a hard and arduous task, but Kyle always tried his hardest to keep Cartman on the straight and narrow. He was proud about the fact that Cartman had indeed shown signs of improvement in his school work since he had started dating him, and he was positive that Cartman held great potential – he really was smart when he tried. The problem was getting him to care about trying. One thing that hadn't changed about him was that he was still lazy and unable to be driven or motivated by anything but food, money, the promise of tasting the tears of his foes, or being able to laugh at others' humiliation.

"I'm sorry, Kyle, but losers don't get to have the liberty of choice."

Kyle's brow twitched as he continued watching Cartman play. He was already three quarters of the way through the level and still not struggling. Kyle's chances of winning the bet were growing slimmer and slimmer and it made him all the angrier that he was the one who had started the stupid bet in the first place. He had brought it upon himself. Still, he was anything if not determined, and he never said no to a challenge.

'If he's not going to lose,' Kyle thought, 'Then I will make him lose.'

Cartman acted like a tough, untouchable, indestructible entity, but Kyle had known him since pre-school, and so Kyle knew that he had more weaknesses than he let on, and one of them was he, Kyle, himself. He was aware that Cartman was quite into him – cared for him more than he dared to admit – and Kyle would be stupid were he not to use that knowledge to his advantage in that desperate time.

Slowly, trying not to smirk and failing miserably as he did so, Kyle reached behind himself and pushed his hand downwards, sliding it past the waistband of Cartman's boxers. On the screen Mario stopped moving and just stood atop a block. Cartman's thumbs had ceased movement.

"K-Kyle?" he asked bemusedly, "What…what are you doing?" Kyle answered by gripping Cartman's cock in his hand and tugging it roughly. Cartman groaned and his hands clenched the controller. "Fuck, Kyle!"

"That's a good idea." Kyle whispered lewdly while he continued to pump Cartman's dick. Cartman groaned again, louder that time, and his head lolled back against his bed he was sat against.

"Fuck." he hissed under his breath, "Fuck, that's good." He let go of the controller to grab Kyle's hips, but froze when he heard it clatter to the floor. His head snapped up, his eyes wide, before they narrowed and looked at Kyle, who had turned his head to stare deviously back at him. "You motherfucker!" he cried, pulling Kyle's hand out of his boxers roughly before reaching around him to pick up the controller again, "You are not winning this bet, you sneaky Jew-rat!"

Kyle huffed and pouted as Cartman resumed playing. Obviously, he had to try harder.

"We'll see about that." Kyle repeated Cartman's previous words, before twisting around in his lap and shifting so that his legs were situated either side of Cartman, straddling him, their chests pressed together. He cupped Cartman's cheeks in his hands and leant forward, to kiss him at the corner of his mouth, to lick at the bow of his lips, to capture his lower lip between his teeth and pull.

Cartman shivered, but he kept looking past Kyle, his brow twitching irately, staring resolutely at the game with a fiery determination that matched Kyle's. Kyle persisted though, and began riding Cartman's lap so that their clothed cocks rubbed against each other. He moaned in a way he hoped was sexy, and he knew he had succeeded when Cartman muttered profanities under his breath.

"God damn it, Kyle!" he whined against his lips, "Stop it!"

"You stop it." Kyle retorted, running his tongue along the shell of his ear before nipping at the lobe.

"Ah, fuck!" Cartman cursed, his thumbs clacking desperately at the controller buttons, trying to resist the temptation to touch the redhead, "You're throwing me off my game!"

"That's the point, genius." Kyle snickered against his neck before sucking a bruise onto it. He pushed his hand past Cartman's waistband once more and took up his cock again, feeling triumphant when he noticed that it was already half-hard. "Mmm," he hummed into the crook of his shoulder, pressing a tender kiss there, "You're so big."

"Fuck you, Kyle." Cartman gritted out, but he didn't sound as angry as he wanted to. He sounded more tortured than anything, as he tried to restrain his own urges.

"I want you to." Kyle breathed, stroking Cartman's cock languidly as he ground his own against it, "I want you to fuck me in my tight ass with your big, fat, juicy cock." Kyle's smirk grew when Cartman's cock twitched in his grasp at his words, and he decided to up his volume. "Oh, Cartman!" he moaned loudly, too desperate to win to care whether Cartman's mom heard, "Fuck me! Fuck me hard!"

He ground himself against Cartman faster, jerking his cock more fervently, panting into the skin of his neck. He gasped and moaned lewdly and pleadingly into his ear, rubbing himself up against Cartman. He even found himself getting a little hard from it all too.

Suddenly, Kyle heard the distraught wail of Mario dying behind him, followed by the sad game over music being played, and he grinned triumphantly into Cartman's neck. However, before he could pull away to laugh in Cartman's face at his victory he found his hips being gripped tightly and possessively. "God damn it!" Cartman exclaimed as he thrust upwards to meet Kyle's crotch, and Kyle gasped, shocked by the waves of pleasure that rolled through him.

He braced his hands on Cartman's shoulder and continued to ride him, the floor creaking as he rose up and thudded down again, moaning as he rubbed against Cartman's dick. Cartman pulled the hem of Kyle's tank-top up in one swift movement and lunged forwards to suckle at his nipple, making Kyle cry out and grip at Cartman's hair, tugging at a tuft of his brunet locks urgently.

"You like that?" Cartman mouthed against the sensitive skin. Kyle bit his lip and nodded ardently.

"Yes," he whispered, "Yes." He forgot how to speak, how to think. Everything was Cartman's mouth, Cartman's tongue, Cartman's teeth, and everything felt fantastic. He made a keening noise and used his grip on Cartman's hair to pull him closer.

Cartman's hands slid lower, his fingers trickling down his sides and around to the small of his back before pushing their way into his boxers and groping his ass, making him cry out again. "So hot." Cartman groaned into his chest. Kyle shivered and his lips parted to let out another shaky moan.

Cartman pressed forwards until they toppled over, so that Kyle was on the floor and Cartman was atop him, trailing kisses along his jaw, squeezing his ass. Kyle wrapped his legs around Cartman's waist and surged upwards, rubbing their cocks together, mentally cursing the fabric that lay between them.

"Fuck, Cartman." he whispered, "I-I need…Fuck."

Luckily they had been in a relationship for a long time, so Cartman understood him perfectly. He hummed against Kyle's neck before biting him, marking him with the signature of his teeth. "Yeah." he agreed, and reached between them to pull them out of their boxers.

Kyle hummed contentedly when he was released from the cotton confines, and he reached up to pull Cartman's face down. Their lips met in a hot, passionate collision, and their tongues swirled together, exploring the caverns of each other's mouth. Cartman tasted of fried chicken and cheesy poofs, same as always, and Kyle would gouge his eyes out before admitting he loved that taste.

They rocked together, rubbing their erections against each other, their tongues battling and their lips moulding. Kyle moaned loudly and happily into Cartman's mouth and Cartman muttered curses back into his. They came like that, practically sobbing against each other's mouths as Kyle cried out loud enough for the whole street to hear and Cartman groaned quietly, his eyes winced shut as stars burst in his vision.

Cartman collapsed on top of Kyle afterwards, both of them panting heavily, and they stayed there for a couple of minutes basking in the afterglow, enveloped in each other's warmth. Cartman lazily kissed Kyle's jaw, and Kyle clung to the cloth at the back of his t-shirt, staring up at the screen, the words 'GAME OVER' upside down from where he laid. He smiled victoriously up at them, and then tilted his head to look back down at Cartman, still kissing his face with closed eyes.

"I won the bet, fatass."

Cartman opened his eyes to glare up at Kyle, and Kyle cried out when he bit his ear as punishment. "You're a sneaky fucking Jew-rat." he replied, his voice caked with loathing. Kyle chortled, because he knew Cartman anything but loathed him, and he pinched his chubby cheeks with a wide grin.

"Since I won," he said, "You have to do your homework."

Cartman sighed and dropped his head, burying his face into Kyle's chest to try and hide from the cruel reality where there was schoolwork to do. "I hate you so much."

"I'll help you with it." Kyle promised, brushing away the hairs plastered to Cartman's forehead by sweat.

Cartman peered up at him, hope alight in his eyes. "You will?" Kyle nodded. It was his job to keep Cartman on the straight and narrow, after all. Cartman lifted his head back up to smile appreciatively at Kyle, and the redhead knew he had been forgiven. "I love you so much, Kyle."

"I know." Kyle flicked Cartman's face in a way that was all too affectionate and smiling at him in a way that was far too fond. "Let's shower first though." he said, grimacing as he took in the sweat-slicked, cum-covered feeling that appeared after the afterglow.

Cartman chuckled and lifted himself up from Kyle. "Yeah, good idea." He got to his feet and held out a hand to Kyle, who took it gratefully and laughed at the rush of being lifted effortlessly to his feet by Cartman. He fell against his chest, still laughing, and Cartman wound an arm around his waist. "Shower sex?" he asked, his voice heightening with hope at the end.

"Shower sex." Kyle agreed with an affirmative nod, and the two of them headed off to the bathroom for round two.

Contrary to the words on the television screen, the game was far from over.

Author's Notes:

This is quite short and lacking in plot, but I wrote it anyway because it satisfies my idea of how Cartman and Kyle hang out when dating: the answer being, same as they would when not dating, except for more closeness and fooling around. I suck at writing smut though, so that's a shame, haha, sorry, guys!
Seriously though, come on, just try to supply me with a more adorable thought than Kyle using Cartman's pudginess as a comfortable armchair. You can't!
Thank you for reading this, and I hope you enjoyed doing so as much as I enjoyed writing it.

Disclaimer: South Park does not belong to me, but to its creators, Trey Parker and Matt Stone. Mario does not belong to me, but to his creator, Shigeru Miyamoto.