Burnin' For You

Title: Sub Cubare (8/?)
Fandoms: Supernatural/Buffy: the Vampire Slayer
Rating: NC-17
Warnings: this chapter Dean/Sam, bottom!Dean, later Dean/Buffy, Dean/Sam/Buffy
Word Count: 4200 (this part)
Spoilers: Season 4 through "It's a Terrible Life"
Disclaimer: I do not own these characters, or any part of Supernatural or B:tVS.
Distribution: With credit only. Recommend away!

Special thanks to my awesome beta dollarformyname for giving me feedback on the porn *g*

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Having spent most of the last several nights on the too-short hide-a-bed, shortly after dinner Sam had claimed dibs on the guest room with unrestrained glee. Since Dean didn't have to be locked up, he could have the lumpy ass thing for a change. Not that Sam's lanky frame fit the guest bed either, but it was an improvement. Though Buffy and Giles had gone to sleep, it was still early for the brothers, and they remained in the family room on the sofa, looking over the Codex and various other books and webpages for more information on the mara.

Dean had been hungry most of the evening. Castiel's appearance had pissed him off, but it hadn't made him lose his appetite. No matter how much he ate, the gnawing in his stomach wouldn't go away. It had actually gotten steadily worse, until it wasn't so much hunger pangs as real pain. Dean set down the book he'd been halfheartedly skimming and leaned back, trying to ease the ache in his gut. He took a few deep breaths in an attempt to relax the tightened muscles.

He glanced over in Sam's direction on the opposite end of the couch. His younger brother was bent almost double over his laptop in apparent interest, strands of hair falling unheeded into his eyes. Something inside of Dean twitched. No, he thought desperately, forcing it to recede. He moved to get up from the couch in the same moment Sam said, "Take a look at this, Dean." Sam gestured to the laptop's screen.

It was a bad idea, having Sam that close, but when Dean edged cautiously closer to his brother, the knot in his gut seemed to uncoil ever so slightly.

"'The mare-witches, also known as the mara, worship the fallen angel Nahemah. The strength of a mare-witch can be judged by the number of horns they have,'" Sam read. "'Most often they possess two horns, occasionally three, and in rare cases four.'" Sam looked askance at him. "Do you have horns, Dean?"

He rolled his eyes. "Doesn't appear that way does it, genius?"

"Idiot," Sam grumbled, smiling. He shoved his brother halfheartedly. The movement pulled his shirt tight against his torso, showing the rippling movements of his muscles. The hunger inside Dean flared again, and his cock twitched. Dean groaned quietly, and tried to pull away. Run away. Get the fuck away from Sam and his own fucked up desires.

A huge hand encircling his bicep stopped him. God, they were friggin' huge. Hell, all of Sam was huge, he thought, wincing as he remembered the night before. He'd sworn to himself that it was just a one-time thing, a bizarre product of what had happened to him. Damn it, he'd felt so much better today. The sensation of Sam's warmth against him made Dean go kind of weak in the knees, and he sank into the sofa in acquiescence.

Something smelled like spring in the room. Sam's nose twitched. Like warm sun and growing things. Like the memory of the first taste of ice cream bought by his older brother as they strolled along the boardwalk of some coastal town. Hot and sweet, and Sam wanted more.

When it happened it was like a switch flipping. The hunger that Dean had been feeling all evening was transmuted to lust in the time it took for Sam to close the gap between them, breathing in Dean as if he were the very air he needed to live. Dean was painfully hard against the denim of his jeans, and pumping out pheromones like there was no tomorrow. If he didn't end this, if he didn't get laid, he was pretty damn sure he wouldn't make it to see tomorrow.

Sam was staring at him, jaw working like he was trying to refrain from saying anything. "Dean," growled Sam through his need, desperately fighting the desire to jump his brother's bones. Hot as Dean was, he wouldn't do this. Dean didn't want it; he'd said as much that morning. Hell, he'd said as much all evening with his body language, keeping distance between them, flinching away when Sam got close.

A physical relationship was playing with fire, and it would end up destroying them. Sam wanted it, though. Burned for it, and not only when Dean's arousal triggered his own. He wouldn't admit it to anyone, but when he thought about it, he'd wanted his brother for a long time now. Since Dean had brought him home from Stanford. Sam was home with Dean, the only home he'd ever known and the only one he wanted now. The most important person in his life. Even Ruby, who knew his darkness in ways he never wanted to share with the brother he idolized, was a shadow in comparison. Maybe he hadn't ever imagined a sexual relationship, but he had craved a deeper connection with the only family he had left.

Sam couldn't move, torn between fear and desire for his brother, and that frightened him.

Dean gritted his teeth as he observed the near panic in Sam's huge hazel eyes. He tore his gaze from his brother and half-ran to the other side of the coffee table, using it as an obstacle between them. He ignored the spasm that almost doubled him over in agony. "I can't stop it, Sam. Get Buffy," he ordered, voice like Dad's and damn if that just didn't put the obstinate fight back into Sam. Dean wanted to die, and Sam refused to go through that again. The first few times had nearly destroyed him, and the last had caused him to seek solace in a demon's embrace and blood.

"No," he spat into Dean's face, voice a husky growl. "She won't come near you." The or else hung unsaid between them, but both felt its weight. Dean was frozen in the headlights of Sam's eyes. Sam stalked closer, his gait almost predatory, spurred on by Dean's fear. The darkness in Sam liked Dean's fear. He checked it back, focusing on how much he wanted to help his brother instead. Sam stepped around the coffee table, so close now that they were almost touching by sheer proximity. He was inhaling deep breaths of Dean. His only thoughts were to protect Dean, to save Dean, want, take, have Dean.

The younger Winchester initiated it this time, whatever it was between them, what he'd been thinking about in the back of his mind all day. Sam's huge hands cupped either side of Dean's face, firm and almost gentle, before he drove his tongue deep and wet into his brother's mouth, claiming him, branding him with a sweet hot iron seared into his soul. When Dean broke the kiss, his eyes were glowing, throwing off sparks of gold in the dim room to provide nearly as much illumination as the table lamp.

"Sam…" he began breathlessly. "Are you sure that it's you that's wanting this? I can't…I can't stop myself. I want…." His voice, harsh from desire and the pain of holding himself back, trailed off into the heavy silence of the room.

The younger man nodded, reaching for the bottom of Dean's now skintight shirt and slowly peeling it off. Each time a new inch of skin was exposed Sam would run rough hands across it, fingernails briefly leaving red weals on the rapidly-healing flesh. Sam wanted to mark his brother up, leave scratches and purpling bruises that claimed Dean as his. Only ever his. "God, Dean. You look perfect," whispered Sam hungrily.

A bitter laugh caught in Dean's throat as he gave himself over to the feeling of Sam. Touching him, marking him up. He would give his brother a ride he'd never forget. The mara in him paced madly in the cage he'd built for it. He couldn't shut down the hunger any longer, the biological need that marked him as something inhuman, but right now he wasn't even thinking about it. His thoughts were caught up in his brother. The sensation of supple skin on skin was heady, and Sam's left hand ghosted across his exposed abs, the other reaching behind him to rest on his ass.

Dean's shirt was rucked up underneath his armpits, his jeans hanging loose and low on his hips. Without warning Sam's left hand dropped to meet his right, and he lifted his brother up and carried him a few feet to the closest wall. Lips and tongues met again in mutual decision as Sam pressed their bodies together, battling for dominance. Sam pressed the advantage of his height and bulk, maneuvering Dean to where Sam needed him to be, and finally his brother went with it, leaning his head back slightly in bliss as the floppy haired brunette thrust against him. Even though their jeans, Sam's dick felt enormous against him.

Sam tore his mouth from his brother's and growled hungrily before tearing Dean's shirt over his head and latching on to Dean's bared neck. The elder man gasped, bucking his hips forward as Sam suckled. The cotton shirt tangled around Dean's arms, leaving them pinned together, not that he was struggling much to get free. God, having him in this position pushed about seventy-five percent of Sam's buttons. What he planned to do to his brother next took care of the rest. He'd warned Dean that he was a kinky bastard.

He laid Dean down face-up on the couch, tugging his pants off in a single smoothly efficient motion. The elder would have made a comment to express his profound shock that Saint Sammy had perfected that particular move, but all rational thought was forced from him when a wet heat surrounded his cock. Shocked, Dean realized that his baby brother had taken him into his mouth. Dean's back arched and he grabbed the armrest behind his head to anchor himself. Dean had had more technically proficient, but this was different. This was Sammy. Sam was sloppy but enthusiastic, and Dean was already hyper-sensitized.

As Sam ran his tongue along the underside of his brother's cock, Dean's eyes lolled back in his head and a groan fell from his lips. Sam pulled away for a few brief seconds to grin a devilish smile. Yeah. Sam knew exactly what he was doing to Dean. God damn.

"Son of a bitch!" whimpered Dean as Sam's hand curled around the base of his dick and jerked it in short firm pulls in time with the motion of his mouth. Dean didn't have a monster the size of Sam's but he was still shocked at how much his brother was able to swallow. He shook with the effort it took not to thrust the rest of the way inside, but he couldn't bear hurting Sammy.

With his other hand, Sam fondled his brother's balls, rolling first one, then the other. Dean's eyes were blazing meteors, lighting up the whole room with their eerie amber glow.

"Sammy…" he moaned, long and low and drawn out, his voice like Sam's old ratty teddy bear and sugar cereal with too much milk and all the things that Sam recognized as home. "Sammy, I'm gonna…." Dean was giving his brother time to pull back, but Sam didn't budge, instead taking a firm grip on Dean's ass and sucking his cock for all he was worth. Dean couldn't hold himself back any longer, and came hard, exploding in his brother's mouth. Sam tried his damnedest to swallow it all, but when he looked up at Dean, the blonde could see the pearly moisture that was running down his chin.

Sam just smiled, wiping his mouth with Dean's shirt, the bastard. He looked amazingly debauched, lips swollen and eyes half-lidded, and Dean wasn't sure if he'd ever wanted anyone more. His brother drew his own t-shirt up his muscular torso and over his head. Sam then returned his attention to his brother's body, running his tongue lower than before, past Dean's balls, lifting him up slightly to get a better angle on his goal, the puckered pink hole of his brother's well-muscled ass.

Dean jerked in surprise when the tip of Sam's tongue came in contact with his opening, but the hungry need was still riding him and he wondered what it would be like to have Sam on top of him, inside of him, riding him to orgasm. The idea of giving himself to his brother completely made Dean hard again almost instantly. His forehead felt hot, and he knew that the four tiny spiraled horns had come out to play.

Sam's voice was low and lust-filled. "Four. You just had to be the damn king of the mara, didn't you? Lying bastard," he chuckled huskily. "Your horns are fucking hot, dude. I—I need you so fucking much, Dean. I don't have any lube, so we're going to do this nice and slow, okay?"

Dean cocked his head at his little brother. Lube? "Just how many times have you done this, Sammy?"

Sam shrugged. "More than once. Plus, Jess liked anal."

"I knew I liked her for a reason."

"Here dude, turn over." Sam's voice was coaxing and firm. Dean latched on to it like a life raft. He was fully naked and spread underneath his brother, who at least still had his pants on. Yeah, so he was a bit nervous. Don't judge. Sam helped him turn onto his stomach, finally extricating Dean from his t-shirt and throwing it on the ground, wet spot up. Hell, that was one of his favorite shirts, the older man thought mournfully. His stomach gurgled and a wave of pain passed though him. Dean gritted his teeth and rode it out, trying not to let Sam see.

"Gonna take care of you," his little brother promised. He'd positioned Dean with one leg on and one leg off the couch, ass exposed. Sam carefully spread his cheeks wide and leaned in to lick his way from the base of Dean's balls to his anus.

"Holy shit, dude!" Dean's whisper was violent and Sam started to back off. "Don't you fucking stop," ordered Dean.

Sam chuckled against the skin of his perineum, and Jesus Christ on a freaking pogo stick the vibration was like nothing he'd ever felt. His cock swelled even more, and he rocked his hips into the couch. Sam gripped his buttocks tighter, warningly. Regretfully, Dean stilled. He was rewarded with his brother's tongue probing gently at his opening.

He was slick with saliva and Sam's tongue slid inside easily. "Fuck. Fuck. Fuck," whimpered Dean in bliss. "Is your tongue as long as your cock, Sammy? God damn."

Sam laughed again, the rumbly vibration going directly to Dean's dick. He was half-surprised he wasn't putting a hole in the damn couch with how hard he was. Sam was fucking him with his tongue, long, deep strokes with a tempo that was still leisurely enough to make Dean impatient. He felt good enough that the pain of a few minutes ago had faded to a dim memory. He was doing what it wanted, what it needed. Everything had to eat.

Sam's hands caressed up his back as he withdrew his tongue. Dean was boneless, totally peaceful, and his brother's warmth felt so good against his skin. Sam climbed carefully up Dean's body, distributing his weight across his brother's form. His jeans were rough, scraping gently over Dean's ass and legs. "You're pretty relaxed, man," Sam breathed in his ear, "but I want to make sure you can take me, okay?"

Dean nodded. He thought that he might have agreed to anything right about then. Sam stuck his middle finger in his mouth, swirling his tongue around the digit. When it was thoroughly spit-slick, he reached down and inserted it slowly into Dean's ass. Dean tensed up at first, but Sam murmured gently in his ear and he slowly unclenched his muscles. Sam's finger seemed impossibly long, and Dean worried not for the first time where this was leading. Was he really going to let his little brother fuck him? Yes! The mara inside him was eager for exactly that. It wanted Sam, and damn him to Hell, so did he.

Sam was busying himself with sucking hard against the skin of Dean's arm. Right where Castiel's handprint used to be. Kinky bastard.

Dean gasped as Sam's finger stroked lightly across something inside of him. His brother grinned wickedly and did it again, pushing forward with increased pressure. "Sam!" cried Dean, voice harsh.

"Shhh," murmured Sam against Dean's ear as he slid a second finger into his ass. "We don't want to wake Giles up, do we?"

"What about Buffy?" moaned Dean, half-curious and half…oh fuck, was that anticipation?

"Maybe later," Sam promised. "Right now you belong to me Dean, and I'm going to make sure everyone who looks at you knows it. Gonna fuck you so hard you'll be walking funny for days."

Sam transitioned from slow shallow thrusts with both fingers to a scissoring motion, stretching the muscular ring still further. He'd never imagined anything as good. When Stacy Phillips had stuck her pinky in his ass while giving him a blowjob freshman year it had been alright, but this? Holy fucking god damn shit. And Sam hadn't even gotten to the main event.

The younger man abandoned Dean's muscular upper arm, trailing kisses and the occasional bite down his back until he reached his brother's buttocks. With the hand that wasn't up Dean's ass, he slapped the exposed cheeks forcefully, leaving a hand shaped patch of reddened skin.

"What the fu—" Dean's protest was cut off by Sam's hand across his mouth. Sam curled his fingers against Dean's prostate once again and stifled a laugh as his brother went cross-eyed.

"Get on your knees," ordered Sam, moving to help Dean into place. God he looked so hot, like an invitation to sin. Dean was propped up on his elbows with his knees underneath him, pointing his ass to the sky.

Sam stroked him a few more times from that position before withdrawing his fingers. Dean mewled at the emptiness he felt at his brother's absence. He heard a rustling of cloth behind him as Sam shimmied out of his jeans and boxers. "It's okay, Dean. I've got you," he said before spitting into his hand and using the saliva to coat his dick.

"Ready?" asked Sam, locking hazel eyes with the luminous amber of his transformed sibling. Mara? Whatever. He really didn't care, he was just Dean and Sam needed him almost desperately. And yeah, it wasn't only the pheromones talking, wasn't even mostly the pheromones talking.

He'd never really been able to tell Dean about what had happened on all those Tuesdays, watching him die over and over and over again. How it had shredded him inside. How he'd promised himself he'd never let it happen again. How he'd stood helpless as the hellhounds devoured his brother and made him spend endless months believing that this time…this time was forever.

Having Dean back, having Dean? Was a goddamn fucking miracle.

When the head of his brother's dick touched Dean's moistened anus, he didn't care what he was either at that particular moment. Sam's cock was barely brushing his ass, teasing and driving him mad with want. He just needed Sam, filling him, feeding his hunger.

Dean bit his lower lip and nodded up to Sam, luxuriating in the anticipatory sensations that having Sammy's cock teasing his entrance evoked. There was less resistance than he'd thought there'd be, he noted as Sam slowly rocked his way into him. It hurt for the first few seconds, before Dean willed himself to relax. The sensation became heat, igniting the furnace of lust he'd been trying like hell to keep banked. Sam's cock was splitting him open, and his body was responding, welcoming the intruder. The blood suffusing his own equipment was putting Dean into a state of euphoria, and he knew it was the closest to Heaven he would ever come.

Dean didn't really have a grasp on the internal components of male anatomy, but he just knew that somehow when Sam reached underneath Dean's leg and pulled it into a different position, the angle shifted just enough, and his brother's cock was sliding against the sweet spot inside of him.

"Fuck, Sam," he whispered roughly. Each stroke against that sensitive knot pushed Dean closer to fulfillment, and he hadn't even touched his dick. He could tell from the way it built, slow and powerful, that it was going to be the mother of all orgasms.

"God Dean, you're so tight. Feel so good. Never gonna leave you, not ever." Sam's voice sounded fierce and as fucked-out as Dean felt. His pace quickened as he approached his climax, his strokes changing from slow, deliberate thrusts to hard, deep lunges of his hips, driving himself as far into his brother as anatomy would permit. "Need you to feel me," Sam said as he wrapped a gigantic arm around Dean's torso in a possessive hug.

"Christ, Sam. I feel you," he acknowledged.

Sam was beyond the capacity for words, unable to respond to his brother. He reached around, grasping Dean's cock in his right hand and jacking it in time to his thrusts. Dean's response was strangled, and he bucked against Sam's hips, driving him even deeper. Sam cried out, coming. A flood of semen and something far more potent smashed into the blonde and all of a sudden Dean was so damn close, and he wouldn't let Sam be finished yet. He had new tricks up his sleeve since he'd become mara and through sheer force of will he commanded his brother back to full hardness.

Sam gasped in surprise, but he couldn't help but do what Dean wanted, even though he was exhausted. Sam understood that that was the danger of the mara's feeding. He felt drained, and imagined that any other person would have been on the verge of collapse, but there was a well of strength inside him. He was usually hesitant to draw from it, fearing the corruption Azazel planted, but he needed it now. His demon blood could shield him and give him an extra reservoir to draw from.

It was Dean's nature now to draw energy from his partner. It was like breathing for him, instinctive and primal and natural. It happened with no need to think about it—his body simply performed the tasks necessary for survival. There was no switch going off in his head, helping him figure out how to use the power; it was just a part of him, and he couldn't control it if he tried. Not that he was thinking about controlling himself. Not with Sam hard again inside him, skin hot and so damn velvety smooth.

"Harder, Sam. I won't fucking break," he cursed, and Sam thrust harder, almost fully withdrawing before slamming himself back in, filling Dean up. Sam's hand tweaked one of Dean's erect nipples while the other remained around his cock, jacking him in time with his thrusts. Dean's orgasm built like the incoming tide, waves crashing against the core of him, each bigger than the one before. Finally, finally he couldn't take any more stimulation and spilled himself over Sam's hand with a roar of satisfaction.

Released from Dean's compulsion, Sam's dick surged again inside his brother's ass, spending a second time. Warmth suffused Dean like pure energy filling him up, leaving him alert and energized. Basking in the afterglow, he didn't even notice Sam collapse beside him, back to the rear of the couch and one arm draped around Dean's waist.

Dean at last felt the hunger inside him start to release the vice grip it had around his gut. It felt like every part of him was relaxing when he hadn't realized they were tense. He looked down at his younger brother, whose breathing was so shallow, so slow he almost looked dead. Dean had several moments of blind panic interspersed with self-hatred. Neither emotion was a stranger to him.

The blonde's traitorous memories took him back to Cold Oak, to Sam crumbling to his knees in slow motion before Dean's eyes, his brother's blood seeping out though the wound in his back, spine twisted and broken. Dean turned his body so that he was chest to chest with Sam, gathering the larger man in his arms and damn it if he didn't want to start crying right there. Shit, and he called Sammy a girl.

"'m fine, Dean. Sleepy." The words were low and breathy, like Sam didn't have the energy to form a full sentence. While normally Dean would take that as a compliment to his bedroom skills, he didn't trust what he'd become. He moved to get up from the couch, but Sam grabbed him around the waist, pinning him in place. "Promised me the bed, jerk," he murmured.

Dean just smiled. "Pretty sure you'd fall on your face before you made it five feet, bitch."

Sam made a noise that may have been assent and simply curled his other arm around Dean.

Fuck, thought Dean. He hated being the little spoon.