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“Okay, Sammy?” Dean asked. He breathed out, keeping his hands steady. It was a delicate spot. Sam looked down at where his brother was working. His eyes were dark. They flashed like the point of Dean’s needle.
“I’m better than okay. Keep going.”
The first time Dean stitched a wound he was 10 years old. Dad had a nasty gash over his kidneys after a ghost threw him into a gravestone. It was too far back for him to reach himself and so he’d handed Dean the needle and said, “Do your best.” Dean’s best had been bad enough that John wore the scar till the day he died; a fat, uneven caterpillar that crawled out the top of his waistband and unfailingly drew Dean’s attention on the rare occasions when he saw his father without a shirt.
His technique had improved with practice. The scars that ran over his and Sam’s bodies now were subtle things, thin white threads that could only be seen up close. When they met the doc, he had looked like a cartoon Frankenstein’s monster. Sam still looked like Sam.
Or maybe Dean had just forgotten how things used to be. Maybe other people would look at Sam and see something very different.
He finished the last stitch and tied it off; ran his finger over the neat line he’d left, curved across the top of Sam’s crotch. The muscles tensed in Sam’s thighs and his hands flexed against the table. When Dean looked up, his brother’s mouth was open, wanting. He stepped forward, leaned over and kissed him.
It was difficult to know how strange they looked because they kept to themselves so much these days. They needed to; had to avoid the questions that would inevitably come once people realized how long the Winchester boys had been hunting together, the fact that they hadn’t aged past their twenties. Dean was sure that there were rumors. But they kept moving, kept killing monsters, and no hunter had come after them yet. Maybe people didn’t believe they existed. Maybe they were scared.
Whatever the reason, they were more isolated now than they had ever been. Just the two of them. Sam and Dean, forever. It was exactly what Dean had always wanted.
Coming back to the house where it started was a risk, perhaps: it was the only place they visited regularly, the one fixed point in their unending, looping journey around the United States. But they had their equipment there, expanded and upgraded from the doc’s original setup; surgical instruments and chemical fluids and an industrial-grade freezer, which they’d hacked to run illegally off the local grid. More than that, though, it was the place where they’d fucked for the first time; right after they’d made the final commitment, injected the formula into their veins and felt it spreading through them, cold and strange.
“So this is it,” Sam had said, his eyes wide and terrified.
Dean had echoed him. “Yeah, Sammy. This is it.” There’d been a long moment of silence when their eyes had met, and then Sam had reached out, his fingers twisting in Dean’s shirt; and Dean had slid his hands over the hot skin of Sam’s torso, and that had been it, they were grappling together on the floor, hands and mouths all over each other however they could reach.
Dean leant over the table where Sam was lying now; gripped Sam’s hip, dug his fingers into the meat of his brother’s ass. He kissed Sam’s chest, tracing his tongue over the lines of stitching that traversed it. Sam bucked upward.
“Get up here, Dean,” he said. “Come on.”
When you’d committed to spending perpetuity with your undead brother, it turned out to be pretty hard to think of reasons not to fuck him. Social nicety? Government laws? They were defying the laws of nature. And so they had this - Dean had it - an eternity with Sam, to have him any way he wanted, any way he could think of. You could do a lot of fucking if you had forever to do it. They’d boned in every state in America, ten times over; big beds, small beds; against walls, floors, roofs; under trees, under the stars; in the river, the desert; in every position Dean had ever fantasized about and a bunch he’d never even pictured.
That was Sam’s influence. Dean’s brother was way, way kinkier than Dean could have imagined before they started this. When he’d thought about it (which he did, much too often, all through their teenage years and into his twenties) he’d categorized Sam as maybe one step up from a virgin; a few fumbles with some sweet girls before college, then that long-term thing with Jess. The night his brother spent with Madison might have tipped him off, but Sam didn’t know she was a werewolf until after. At least. When he looked back on it now, Dean wondered whether something in Sam had responded to that part of Madison that wasn’t human; the feral part, the part with teeth.
Dean stood up and unbuckled his belt; let his jeans drop to the floor and stepped out of them. He climbed up onto the table and straddled Sam’s hips. He pulled his T-shirt over his head. Sam looked up at him, grinning. Hungry.
“You ready for this?”
Taking the medicine, turning themselves into whatever they’d become; that had freed Dean from the constant, nagging fear that Sam might leave him. After a while, he’d figured out that it freed up something in Sam’s mind, too. If Dean worried about loneliness, abandonment, Sam worried about being a freak. He worried about being a monster, a creature that Dad couldn’t ever quite love, a danger that Dean would have to put down. He worried that there was a part of him Dean wouldn’t ever accept.
Except now, they were both of them a Frankenstein mess of parts. Dean had a skinwalker’s liver inside his abdomen. Sam was breathing through lungs they’d hacked out of a warlock. They were more monstrous - less human - in their half-life than Sam had ever been alive.
It just made sense to embrace that.
Sam was a genius. That was the thing. Dean would never have thought of this. He hadn’t caught onto it on the evening three years ago when Sam looked over his shoulder at the writhing, animated bodies onscreen and said, “You know, there’s supposed to be a giant squid-man in Lake Michigan;” or the day, two weeks later, when Sam directed the car north. He hadn’t figured it out when they were sitting on the rainy shore, the squid-thing dead on the beach in front of them, skewered on his brother’s harpoon. Even when Sam pulled out his long, thin whaling knife and told Dean to fetch the cooler, Dean had said, stupid, “We’re good for parts.” Dean kept an eye on that stuff. He was good at it. It was the same as maintaining the car. He knew when bits of Sam were wearing thin the same way he knew when Baby’s oil needed changing. He hadn’t thought about switching for fun. Why would he? It was only in the car back to the motel that he’d put the pieces together; the video, the hunt, the smirk on Sam’s face.
He wouldn’t have let Sam do it, if it were the car. But when Sam had taken the tentacle-dick off ice, Dean’s second-hand heart had stuttered and he couldn’t say no. He’d shaken, taking off Sam’s own dick; laying it tenderly in the cooler’s embrace. He’d been terrified. What a dumb, crazy idea. What if Sam couldn’t ever have sex again? But he’d pushed on, pushed through, summoned his best surgical skill. When he’d finished the last, careful, tentative stitch, the thing had lashed like a whip, suckers twitching, and Dean had almost come in his pants right then.
Sam stuck with the regular look most of the time; Dean almost always, although he did once try out a schlong from a demonic porn-star that was just too big to resist. But they were a long way from being done with experimentation. Sam’s imagination was boundless. The words “So, get this,” had started to have a Pavlovian effect. Dean didn’t know, most of the time, what he was letting himself in for; Sam liked to surprise him. But he’d not been disappointed yet.
The dick he’d just finished grafting onto his brother belonged to a serpent-creature they’d hunted down in Nevada; something like a basilisk, with a name that Dean still couldn’t pronounce. The dick was forked like a snake’s tongue, lightly barbed. It was designed to fit into the parts of the female, that’s what Sam had said. It wasn’t made to fit into Dean. But he was going to take it anyway. He’d not met an appendage yet that he didn’t like, not when it was attached to Sam.
Sam frowned, concentrated, and the points of the thing at his crotch flexed and twisted. One side moved away from the other, wriggled. He could move them independently.
“Christ, Sam.”
“You ready?”
Dean was ready; they’d learned to get him open before they did this. Neither of them liked to wait. He ran his palm over the unfamiliar skin of Sam’s dick - dicks - whatever. The texture was different, almost rubber-like. That was okay. Dean was developing a connoisseur’s sense for the textures of what went into him; slick, scaly, spiked.
It might not be only blood flowing through his veins right now, but whatever it was, every drop was responding to the vision before him; the sensation of Sam stiffening under his hand.
“Okay,” he said hoarsely; rose up on his knees. Sam leaned forward to guide the cock into Dean’s ass. Dean took it slow, feeling the strangeness of it; the nodules pushing at his insides, stretching him, flexing against him like a fistful of fingers. He shuddered, exhaled a shaky breath; leant forward, his hands either side of Sam’s chest. A frown still creased Sam’s forehead. He was concentrating, exploring, figuring out what he was able to do.
Dean hadn’t thought too much about it but he realised that Sam was only half-inside him when the other half of the dick curled around to brush over his perineum, a careful touch. Dean flexed his muscles, tightening around the bulk inside of him. “You can,” he said. “You can put them both in.”
He could remember a time when Sam’s mouth had been sweet strawberry-pink, red and wet and inviting. They were both of them paler now, blue-tinted, but he didn’t want to taste his brother any less. He leant forward, nipped at Sam’s lips. “C’mon, Sam,” he said. “Get that freaky thing inside me.”
Sam laughed. Dean felt a pressure at his entrance, probing cautiously; reached back and slid a finger into himself, gave Sam room to squeeze in. Oh, yeah. This was the good stuff. His skin was straining. He felt full, stuffed. He loved that sensation. Sam knew it. They’d borrowed the knot from more than one of the werewolves they’d killed. Dean still thought fondly of the black dog they’d taken down in Nebraska. He’d not been able - literally, not been able - to walk for a week after that one. Sam hadn’t been happy about it. Dean had been delighted.
There was movement inside him, a sweet brush over his prostate. Sam was - Dean wriggled, thinking about it - Sam was pushing the forks of the dick in opposite directions, stretching Dean out inside. It felt. It felt. Dean choked out a sound, incoherent. It was only then he felt Sam’s hand on his dick.
“Fuck,” he said, “Fuck, fuck, Sam.”
Sam smirked and curled his fingers tighter, drawing his hand toward him, coaxing Dean higher. The twin ends of the dick inside Dean shifted against each other. Double penetration. Dean’s breath rattled, strained.
“Come on,” said Sam, jerking him. “Come on. Feel it, how strange it is. You get off on it, right? Your freaky little brother.”
“Yeah,” Dean said. He flexed his thighs, shifted upward, felt Sam tug him back down from inside. “Yeah, fuck. Sam, you’re so, fucking - you’ve never been -”
“I’m a monster,” Sam said evenly. Dean’s balls throbbed heavy. “And what does that make you?”
“Monsterfucker,” Dean said. “I’m a. I’m.”
“Yeah, you are,” Sam said. He darted a tongue over his lips; not his own tongue. This was long, forked. He leant forward and it, the tongue, kept coming; flickered over the head of Dean’s dick. Dean curled forward and came. His jizz was thin, watery. Sam lapped it up. Nothing about them was the same, none of their bodily fluids. But it still felt good. It was better than any sex Dean had ever had in life.
Sam was still moving inside him and Dean sat upright at last, worked his thighs properly, bouncing his brother to completion. It didn’t take long. Sam arched back off the table when he came and the things inside Dean stiffened taut, pushing at his insides, hurting almost. They were both sticky and panting when Dean climbed off. Come slid down his leg. It was white and cloudy, not so different than a human’s.
“Snakes lay eggs, you know,” Sam said. Dean couldn’t control his expression. Sam started to laugh. “I’m messing with you. That’d take a lot more surgery.”
“Yeah,” Dean said. No way. Although. There was something about the bulk of it, the idea of an egg inside him, that appealed. “No way,” he said again.
Sam lay back on the table. His stitches shone in the lamplight, a network criss-crossing over his body. “Don’t worry. I still have plenty of ideas.”