Title: As They Expand (the Pulmonary Remix)

Rating: R

Pairing: HET. Dean/OFC

Warnings: Spoilers for 3.11, Mystery Spot

Note: Written for the intriguing and terrifying Kamikaze Remix over on LJ.

Original story: With One Eye Open by chemm80

:::

Dean's lungs start to ache about ten miles out from Broward County, where billboards advertising the Mystery Spot still dot the sides of the highway. Beside him, Sam sits straight and silent in the driver's seat, and Dean rubs his chest as he watches the blood slowly leech from under the skin of his brother's knuckles.

"You hold on any tighter you're gonna strangle the wheel," Dean remarks, and Sam jerks a little like he wasn't expecting the sound of another voice.

"Sorry," Sam says, but he doesn't loosen his grip.

:::

Sam is six years old and they're sleeping in the Impala by the side of a field in Missouri. Or, Dad and Dean are sleeping – Sam is wide-awake, hot beneath his scratchy wool blanket and staring at the outline of tall grass as it brushes up against the backseat window. The late summer wind sighs around the contours of the car, and John is a dark shape in the front, slumped against the wheel, his shoulders shaking as he snores under his leather jacket.

Sam turns to look at Dean, stares at the damp patch on his sleeve from where his head is pillowed on his arm, mouth slack. The moon is almost full and the stars are bright, and in the dim half-light Dean's pale skin looks translucent, eyelids a dark smudge in his face. He's very still, stiller than John, and Sam waits, watches for the telltale movement of his brother's chest.

But Dean is motionless.

Sam strains his ears, but all he can hear is the hum of cicadas, his father's rhythmic snores, and the sound of his own breath: a swish as he breathes in, a huff as he breathes out. From Dean, nothing. Silence.

Sam's heart jolts a skittered beat, and the dark quiet of the car suddenly takes substance and presses down around him like two hands shaping a dome from wet sand. He scrabbles out from under the blanket and leans over his brother, face just five inches away from Dean's face, and he sucks in a mouthful of air and then holds his breath, fights to keep from making a sound as he listens.

He thinks he hears something but he can't be sure, and he wants to shake Dean, to wake him, but all of a sudden he is absolutely petrified of failure. Terrified that he will put a hand to Dean and Dean won't wake up.

Sam is still holding his breath, growing lightheaded from fear and lack of air, and he curls a hand over his brother's sleeve, listens as hard as he can but still doesn't hear anything. He tastes the salt of tears seeping between the seal of his lips, fan feel his eyes burn and blur. He watches as a drop falls from one eye and plops onto his brother's cheek, trickles down towards Dean's open mouth.

Suddenly Dean stirs, shifts, and Sam pulls in a noisy, surprised gulp of air that rushes into his lungs so fast it hurts.

"Sammy?" Dean mumbles, crinkles up his face in annoyance. "Get offa me."

Sam can't speak, is too overwhelmed with relief, too dizzy, and Dean does a double-take, squints at his brother in the dark and reaches out a tentative hand.

"Hey," he whispers. "What's wrong? Were you – are you crying?"

"No," Sam says, and kind of faceplants into his brother's shoulder.

"Ugh, Sam," Dean complains. "I can feel your snot." But he doesn't move. "Did you have a nightmare?"

"I thought you weren't breathing," Sam whispers against Dean's shirt. "I thought you were dead."

"What? You're a weirdo," Dean says, shifts a little so Sam is tucked under his arm. "I'm breathing – you're just fwightened 'cause it's dawk and scawy."

"I am not!"

"Scaredy-cat, scaredy-cat, scared of the dark," Dean taunts, and Sam punches him hard in the leg.

"Ow, you stupid baby," Dean hisses. "Go back to sleep."

He doesn't push Sam away, though, and so Sam burrows against him, wriggles around till he's comfortable, Dean muttering sleepy protests 'til he settles down. Dean's arm is a little too heavy across his back, hot and constricting and a little suffocating – but Sam doesn't mind. This is how he wants it: his brother's chest rising and falling under his cheek, Dean's steady breath ruffling the top of Sam's hair.

But even when he drifts into a restless sleep, he's still afraid.

:::

Four days out of Broward County and Dean is in the backseat of the Impala, his mouth fastened on the pulse point just above Erica's tattooed collarbone, one hand tangled in the hair at her neck and the other reaching between their bodies to pull aside her short black skirt.

Above him she's gasping in short, silent bursts of air, and Dean's goal for the foreseeable future is to get her to throw a little vocal action behind those gasps, change them into moans. He crooks his fingers, not quite inside of her but pretty damn close, and there's that first little oh, almost surprised, and she moves her hips against him in a way he very much appreciates.

Outside the car a door slams from far away, from one of the motel rooms on the other side of the embankment, and Dean has a sudden flash of worry that it's Sam coming out to check on his brother – and christ, Sam is the last person Dean wants to see, or to be thinking about, but now that he's thought about him he can't shake it: Sam's fretful, creased-forehead face superimposed over Erica's half-lidded eyes and sweet, bow-shaped lips, and Dean groans against the soft skin of her neck. It's not the good kind, though – it's the kind of groan that comes when you can feel yourself losing wood because you're thinking about how your brother's not twenty feet away, worrying himself retarded in some shitty motel room.

Goddammit, Sam, Dean thinks, tries to focus on the smooth curve of Erica's breasts underneath her black tank top, tries to focus on how wet and smooth she is against his fingers, how good she tastes, how good she'll feel, and Sam's presence slips away. It all slips away as she leans back to tug off her shirt and then shifts purposefully against his hand, breathing hard as she reaches for the buttons of his jeans. She hits her head on the roof of the Impala as she straightens, and grins down at him, bright and free and alive.

"I haven't had car sex since my freshman year of college," she says. "And I'm not even gonna think about how long ago that was, god."

Dean, impatient, pulls her back down and fits his mouth over hers, holds the kiss as he fumbles his jeans down with one hand, and she reaches down to help him, pushing and pulling his boxers down off his hips, then sitting back against his legs so she can tear a condom open – and no matter how many times Dean sees it, watching a women sink her teeth into something that's about to be on his cock is always fantastic.

This, Dean thinks – this, right here. Maybe he'll just do this for the next few months. Fuck hunting, fuck eating, fuck sleeping – just fucking. It's the only goddamn thing he can do these days where there's a definite, satisfactory end – the only thing he can do where he knows he's gonna win.

He used to like driving, but these days it doesn't fucking matter where he goes – his end location's gonna be the same no matter what. He used to like cleaning his guns, but there's nothing he can shoot at that'll keep him from going where he's going. He used to like a lot of things, things he didn't even know he liked until all of a sudden he didn't anymore… but this? This, he's always gonna like.

Erica smoothes the condom down over his cock with practiced precision, and he bucks up into her hand, hisses a little. He was planning on a little more foreplay, to be honest, was planning on replacing his fingers with his tongue, but she has other ideas, apparently, and that's fine by him, absolutely fucking fine, oh, god, so totally fine

Erica shifts a little, lifts her hips and then sinks down sloooowly onto him and Dean's brain whites-out, zeroes into a two-foot radius, and this is why he should just fuck until he dies, literally, because when he has this he doesn't think about Hell and he doesn't think about Sam, pale and clench-jawed alone in the motel room, unreachable – too many Tuesdays stacked between them, too many years and too many sacrifices and they don't even really speak to one another these days, these last days, and ever since Broward County the weight of Sam's fear has been crushing, his overprotection like a physical thing that is settling itself onto Dean's chest, surrounding him at every moment and pressing down until he can't breathe, hasn't taken a good, full breath for four days, his lungs seized and immobile, that new, strange way Sam looks at him now, eyes militant-hard and unfamiliar, controlled and constricting so Dean can't breathe, he can't breathe, he can't breathe…

Above him Erica comes with a shudder and a quiet moan, and he follows a second later, gasping for air, his body having followed the motions even though his mind was far, far away – and goddammit, even this has been taken from him, even this, fuck.

Erica is collapsed against his chest, mouth pressed to his neck, sweaty hair tangled up against his skin, and he tries to pull in a breath, but she's too heavy against him, weighing down on his chest, and he feels an itchy thread of panic lace through his body, just wants her off.

"Sweetheart," he says after a few moments, when he can't take it anymore, "I've gotta take you home."

"Ah," she says ruefully, pushing herself up to look down at him. "I forgot this part of doin' it in the car."

"Yeah," he says, doesn't have the energy for much more.

They get dressed, mostly, clean up a little, and Dean takes her to her apartment, waits outside until he sees the lights go on in her window. Then he drives back to the motel, parks the Impala in front of their room and tries to figure out if Sam's awake or not. Everything looks very dark.

But when he comes inside, Sam is lying on top of the covers, and he sits up as Dean eases the door closed behind him. The room is dim and Sam is just a shadowy shape, his teeth and the whites of his eyes the brightest parts of him.

"Hey," he says, doesn't even feign sleepiness.

"Hey," Dean says, hesitates before reaching to turn on the overhead light. Two of the lighbulbs are out and the yellow glow is hazy, indistinct. Sam blinks a little.

They don't say anything else, and Dean goes into the bathroom to brush his teeth and change, wash up. He can feel Sam listening and waiting on the other side of the door, and he feels a flash of impotent fury, not at Sam, precisely, but around him.

When he comes out Sam is still sitting upright in the bed, his broad shoulders squared. He's staring at the wall, that blank, hard-eyed gaze he's had since Broward County, and Dean's not entirely sure where it comes from but he knows it scares him.

"I'm going to sleep," Dean says, tries a leering grin, "I'm wiped out," but Sam just swallows and nods, waits 'til Dean is positioned under the covers before turning his lights out.

Sam's boots are still on. His boots are always on.

:::

When Dean was a kid he used to have this dream: he would be watching Sam from far away, and Sam would be standing at the edge of a huge cliff, sandy and red like the mesas of Arizona, silhouetted against a razor-blue sky. The air was hot and thick, so thick Dean could barely move, had to push against it just to take a step, and Sam toed the edge of the cliff like he had no choice, looked towards Dean and shouted for him. And Dean would push through the air, and it would push back against him, and Sam would shout for him but Dean couldn't shout back.

And Sam never fell off the cliff, but Dean never reached him, either.

:::

Dean wakes to find Sam crouched above him, face rotten-potato pale, one hand curled in the collar of Dean's worn grey t-shirt.

"Oh thank god, thank god," Sam babbles as Dean cracks his eyes, struggles to focus. "I thought you stopped breathing, Dean. I thought you weren't breathing."

"What?" Dean croaks, struggles upwards, Sam's big hand falling from his chest.

"You were blue," Sam says, trembling slightly, and all of a sudden the hard-eyed, controlled look is gone and Dean can recognize his brother again.

"I was what?"

"You weren't breathing," Sam repeats. "I thought... I thought you stopped."

Dean takes a deep breath, a rattled clearing of already-empty lungs that sends a spike of pain through his chest. Sam is staring at him, waiting, waiting for him to say something, wanting reassurance, but Dean's head is still sleep-fuzzy and he can't gather his thoughts, can't think how to deny what's so incredibly obvious. He takes another breath, looks past Sam's shoulder at the wall, solid and blank in the dim light.

He thinks he might have been dreaming about that cliff again.