Pairing(s): Over the course of the chapters we'll post over the next few days and through Halloween, you'll be seeing Wincest, a dash of Sastiel, Sam/Jess, Dean/Cassie, Denny, Senny, Charlie/Jo, a nice helping of Megstiel.

Genre: Supernatural!Horror!AU … Just in time for Halloween! ;D And who DOESN'T love some Asthma!Sam in their life?

Author's Note: Hello! WincestIsLove from Tumblr here, and this here is the prologue to a very potentially 12-15 chapter'd fic (we already have 7 chapters written, omg) that my wifey Tumblr's scrumptiousalterboy and I are collaborating on here and on AO3! Please bear with us, it's our first foray into legit horror-movie-esque genres, but we hope you'll enjoy the extra spooky in your lives this Halloween season. It has kinks, sex, mystery, violence, and gory deaths. We'll be posting a new chapter on the daily, unless life explodes! XD

Disclaimer: We do not own Supernatural or the characters, we just love them to pieces.

Potential Triggers (over the course of many chapters, not the prologue itself): Cabin In The Woods, Asylum, Blood and Gore, Blood Play, Blood Drinking, Violent Sex, Breath Play, Slight non/con elements later in the story, Suicide, Knife play, Major Character Deaths. It's a horror story, please read at your own discretion, and don't expect happy endings.

IT RUNS DEEP

Prologue

June, 2000

~I see a bad moon arising. I see trouble on the way. I see earthquakes and lightning…~

Creedence Clearwater Revival sang from the tinny radio on the nightstand as Cassie was shoved down onto the bed. Her dark skin complimented the flowery prints of the old comforter, lips blood red and bright. They caught Dean's attention away from the way her breasts jiggled from the fall. He was quick to straddle her down, wrists as fragile as a bird's wing under his hands. His weight pressed her into the bed as her soft ringlets brushed against his forearms. As soft as her naked thighs that held firmly against his own.

"Oh now, that's a pretty sight," he purred and she gnashed her teeth at his nose. Dean laughed, the deep throated rumble soon pressed to that pretty, painted mouth. Cassie melted beneath him a split second before she was straining against his hold. Full hips raised off the bed to grind his hard on against her taut belly. So desperate for him that Dean couldn't help but laugh into the kiss. He got bitten for his troubles.

"So feisty," he tsked in mock reprimand, as if that wasn't exactly why he was with her. Her pearly whites snapped again, telling Dean that it was his cue to hurry up and turn that snarl into a moan. His lips brushed her nose, then the corner of her lips, her neck and down, down to those beautiful, perky breasts. He blew cold air on each nipple to make them tighten into hard, dark nubs before his clever tongue and wicked teeth made her sing. It was the only noise that made him forget to miss the rattle in damaged lungs…

—–

"Sam? Baby, talk to me. It happened again, didn't it?"

It took Sam a few long moments to realize the screams weren't coming from his mind's imagination. It was hard to realize much of anything when you couldn't breathe, but the screams? Those were real. No one was getting hurt, no one was misstepping. The screams were coming from upstairs where his big brother was making it clear he knew how to make a girl cry out in quaking pleasure.

Sam's distant and fogged over hazels blinked a few times between worsening wheezes. Grief washed over him with enough force that all but doubled him over as his grey world returned to one full of color in the cabin's spacious, antique living room, the worried voices of Castiel and Jess there in the room with him. …But they weren't louder than the screams. Cassie was coming now, and he could still all but picture it as it happened.

It felt like someone was twisting a knife into his heart.

"I… can't," he managed on a choked breath, the corners of his eyes stinging and he had to close them against the tears, lungs rattling that much more on his next wheezed breath. He heard Castiel scramble away from the fireplace while Jess pressed her cool palm over his quivering chest, rubbing in the right way. Sam leaned into her touch despite himself, just needing to tell himself it didn't mean anything, it didn't have to mean anything.

"It's fine. I'm alright."

But it wasn't fine, his heart wouldn't stop pounding and his airways were getting smaller. Coughs were taking him over, stealing more of his precious air, and Sam was desperately patting himself down for his inhaler. Where had he left it?

—–

"Baby, please," Cassie moaned, full hips bucking up into Dean's sinful mouth, into the tongue that was destroying her as he ate her out with relish in the wake of her rolling orgasm. She was a shuddering, writhing mess under him, manicured nails raking over his scalp. Dean smirked around her clit and rubbed the oversensitive nub hard enough to make her jerk..

"Need you, I need you in me," Her fingers were desperately curling in his straw blond hair, tugging him up so she could drag his wet mouth to hers in a passion fueled kiss, legs curling around his hips with purpose. Like he could resist giving her what she wanted when she went all wild with lust on him, scratching down his back and rolling her body up against his, flushed with the pleasure he had given her and oh how she wanted more.

—–

Castiel's hand closed around Sam's wrist to pull it forward and place Sam's inhaler in his clammy palm. He and Jess watched Sam with twin expression of worry as he frantically pumped his lungs full of Albuterol. Jess continued to rub his chest and soon Cas helped ease his shuddering diaphragm by rubbing the small of his back. Though it didn't help when Dean's heavy sigh floated downstairs.

"Breathe, Sam. Focus on breathing through this," Cas encouraged.

"Maybe we should take a walk?" Jess suggested. Sam's lungs locked and Castiel shook his head.

"No, it will be raining soon. The others will be lucky as is if they don't get caught in it during their hike. Breathe, Sam."

—–

Her body was liquid fire, tight heat encasing him so good. Dean sighed against her bee stung mouth while soft curls slid over his fingers like silk. He buried himself to the hilt, hips pressed flush with her legs locked around his waist. Cassie always came alive beneath him. He could make her tremble with such impatient need from just a roll of his hips. Not even a proper thrust, an undulation of fluid grace just to feel her clench around him.

She could be cold sometimes, a statue of marble under his touch when they fought, but here, like this, she was all supple flesh and fire and she needed him like she couldn't need any other.

"Gonna make you feel so good," Dean promised, lips brushing against hers as he spoke. He lifted his hips, groaning at the slick, perfect friction as he pulled almost all the way out. "Gonna make you scream…"

A snap from below froze his movements. Dean's senses became hyper focused, his attention no longer in the room he shared with Cassie. Nails dug a warning into his sides but all Dean was concerned about was the whistle in the wind, like Sam's lungs after a particularly bad coughing fit, and another sound.

A dull thud.

"Sammy?" Dean called out without thinking. Naturally, it was the wrong thing to say in bed.

"Are you kidding me?" It was like all the sensual heat and fire between them had been doused in ice water. That's how cold and aggravated Cassie's voice was. She was pure sexual frustration and annoyance beneath him, reaching for Dean's face that had turned to the side to 'hear' to better make him look at her, anger in her dark eyes. He was clearly a dead man.

"Did you really just say your brother's name in bed? Again? Is fucking me something so boring it's that easy to get distracted?" She demanded. Dean had the good graces to flinch.

—–

"No.." Wheeze, nasty cough, another hit of Albuterol, eyes fluttering closed as he tried to get enough air in his lungs to speak, "..walks. No going outside." Not him, not her, not into the storm that was coming.

"Dean would… Spazz, he knows rain doesn't..help.."

Cassie's moan upstairs choked off and then all he could hear from them was talking and it didn't sound none too happy. Sam probably would've felt more relief if his head still wasn't so full of the screams and mental images. Eyes that couldn't quite look at Jess or Cas were still wet with unshed tears of grief he was trying so hard to rein in, trying so hard to breathe through the slowly calming asthma attack and the few rounds of coughs that continued to plague him.

In his peripheral vision he saw the look Jess was giving him and he gave a subtle shake of his head, taking another hit from the inhaler.

"I can't.. Tell him.. He'll think I'm a freak."

—–

Yeah, Dean knew there was no way to salvage that. Cassie was out for blood and Dean couldn't just let it go when Sam might very well be having a bad attack. It didn't matter that Jess and Cas were downstairs, Sam needed him. But Dean should have known better. The air was charged with gathering rain clouds and the damp was always a threat. More so than sharp nails and the wrath of a woman scorned.

"Don't you dare," Cassie warned, but Dean's mind was made up.

"I'm sorry," he said and rushed out of her hold. Her nails caught the left side of his cheek, leaving a hot welt behind, possibly even blood. It was the price Dean was willing to pay as he scrambled for his pants. The bed creaked from shifting weight but Dean was out of there before she could catch him and eat him alive. He had to get to Sammy.

—–

"Sam, you have to tell him. This can't go on any longer," Jess was insisting down in the den.

Dean leaned over the banister to see the three huddled as they usually were on the god awful ugly couch of yellow stained leather and deer antlers. Sam was in the middle and his inhaler in his mouth, Jess's hand splayed carefully over Sam's chest, Cas's under Sam's sweater and on his back. Dean's jaw ticked as a hot surge of frustration washed over him.

"Tell me what?" Dean asked. Three heads snapped up in unison to give him similar 'hands caught in the cookie jar' stares. Aware of Cassie storming out of the room, his eyes locked on Sam's, brow raising expectantly. Sam usually cracked under pressure when Dean gave him that look.

Too bad then that Victor, Benny, and Jo chose that moment to grace them with their presence. The front door flew open and banged against the wall from the force of a harsh wind. It pushed them inside, carrying the scent of impending rain inside the cabin. The damp. Dean squawked indignantly and raced down the stairs.

"Looks like we came back just in time," Victor said as lightning split the sky outside.

It was Sam's saving grace, to be honest, because Dean was then occupied with getting to door closed before more damp air could get in the cabin. Or at least Sam thought it might be his saving grace, hastily getting up from the couch in the hopes of escaping while his brother was distracted, but the damp air had other plans the moment it got into his lungs. It wasn't gonna let him go anywhere.

Sam's wheezes became coughs again just as Cassie was making it to the banister in her bathrobe, looking pissed off with the way Dean was suddenly there on Sam like a bee to honey to rub his chest for him while the boy's fist curled in front of his mouth to cough and try and breathe through it…

And not stare in fascination at the line of blood on Dean's cheek that made his dick twitch. Definitely not that.

"Seriously? It's just a cough. Not an asthma attack, a cough, and you gave up sex. How erotically codependent are you?" She asked, clearly having no qualms with calling Dean out in front of everyone on being so obsessed over Sam's asthma.

"Get over yourself, Cassie," Jo scoffed, rolling her eyes as she pushed a hand through her windswept blond hair, "just because you're an only child princess doesn't mean Dean's suddenly not allowed to give a damn about his brother regardless that you've been sucking his dick for a few months."

Cassie's scandalized sound made the others in the den snicker despite themselves. Just another night up in the family cabin right?

When did this become Sam's life? Working on getting his lungs under control and looking anywhere but at his worried brother('s blood), Sam's gaze landed on the window just in time for his own veins to run cold.

A dark shadow of a figure had darted past, as real as the screams from earlier, and Sam barely managed to get out a wheezy,

"Someone's outside–"

Before the power went out and they were cast into time, Sam wasn't the only one who heard screams.

A/N: We really hope you guys enjoy the spooky and coming horror in this fic over the next few days, and would love to hear your thoughts! Reviews make the world go round! :D