Disclaimer: I obviously don't own Supernatural.
Warning: Implied D/C, language, religious themes.
Note: I recently started watching Supernatural and was instantly hooked. This story started as a prompt-writing experiment with a focus on conveying one theme in three lines. Hopefully, it worked. This is set somewhat vaguely in the middle of S5 because that's all I've seen of the show thus far, but as Tumblr has ruined S6 through what's been released of S7 for me I suppose this is AU after S5. I've found myself strangely interested in the concept of fallen!Cas.
Despite Sam's epic, bitchfaced complaints, Dean says nothing to warn Cas about the concept of recoil. When one long, slender finger squeezes the hairpin trigger of the older Winchester brother's well-loved Colt 1911 for the first time, Dean fights down a rush of bitter pride at naturally uncanny aim and retrieves his gun from shaking human hands that had once dragged him from Biblical fire an brimstone. He blames the cold Nebraska sky and the vivid blue of Cas' flannel shirt for the brilliant cornflower of wide, bright eyes.
Somewhere between mile markers fifteen and thirty-seven, Cas had finally succumbed to a mixture of adrenaline-borne exhaustion and his natural tendency to take up more room than seemed physically possible. Slim frame half-curled, half-sprawled across the front bench seat of the Impala, his thick head of hair is a warm weight against Dean's denim-clad hip as he drives. As the former angel mutters scripture under his breath in Latin, Dean lays a hand atop unruly black locks in need of a trim and picks up the chorus.
At their fifth diner in forty-eight hours, a harassed-looking waitress presides over what has to be the single most ridiculous argument to which Sam has ever been witness. Cas' arms are folded over his chest in a display of classic teenaged defiance undermined only by the almost comical pout on his handsome face, impossibly blue eyes glaring holes of self-righteous fury into the stained Formica tabletop. Dean, the black-hearted hypocrite that he is, has decided that rebel angels cannot survive on a diet of beer and cheeseburgers alone, and it is the first time that someone other than Sam has had to experience the elder Winchester throwing down the proverbial 'big brother card.'
With very few exceptions, awkwardly guiding Cas through the human integration process has been an uproariously entertaining experience. From his first, disastrous foray into the seedy nightlife of brothels to his endearing—the word 'adorable' does not exist in the Winchester vocabulary—habit of watching children's television shows, Cas' awe and trepidation of the trappings of the twenty-first century mortal world are endlessly fascinating. Dean is pretty damned sure, however, that physically pinning his best friend to a questionably clean motel bed and gritting his teeth hard against pained shouts, Sammy digging deep for the bullet slug in Cas' right shoulder, is a fucking exception.
His boys had almost died—again-last night. Bobby isn't sure when exactly 'the Winchesters' category in his head had expanded to accommodate a perpetual five o' clock shadow and wise, loyal blue eyes to match Dean's fiercely protective green, Sam's determined and intelligent brown. The old hunter stands in the doorway to his crowded living room, takes in the dogpile of limbs, flannel, and weapons laying exhausted across worn sleeping bags on the floor, and he huffs a fond, "Idjits," before shuffling off to make coffee.
Sam understands on some innate, subconscious level that he will always come first in Dean Winchester's structured hierarchy of priorities. The youngest hunter has never had a rival for the place of 'most important' in his brother's life. As Cas snags the remainder of Dean's beer without a word of protest or threat of bodily injury, Sam frowns into his cup and prays to no one in particular that Dean is never actually forced to choose.
Sam spends an hour and seventeen minutes attempting to convince a very distraught ex-angel that he isn't dying but has a pretty bad stomach flu. Despite Cas' repeated requests for a bullet to the head, Sam just sits beside his friend in the dismal bathroom of their current motel room and brushes sweat-soaked bangs from where they've plastered to Cas' forehead as he clutches the toilet like the holy grail. Sam does not roll his eyes and comment that fighting for forty years in Hell and then following Dean like a kicked puppy for another four should make the flu feel like a tropical vacation by comparison.
Dean always forgets his own birthday, but he never forgets Sammy's. Sam always remembers Dean's birthday, Jess', and Bobby's. Cas doesn't have a birthday on any calendar in existence, until one night in the middle of an episode of "Cops" when Dean suddenly declares that his best friend was born on, "September 18, 1975, because Jimmy seemed a few years older than me," and though no one in the room mentions the significance of the date, the pride on Cas' face is louder than the wailing sirens on the TV.
It's probably completely irrational and just a little psychotically protective on his brother's part, but Sam really can't find a decent argument in his Stanford-refined brain against Dean yelling at Cas for a solid twenty minutes when he catches the former angel smoking a cigarette on Bobby's back porch. Dean and Cas have explosive, violent arguments about as often as Dean and Sam have immature bitchfights; that doesn't make them any less spectacular. Sam's about two seconds from barreling outside and physically dragging them apart when the haunted gleam in Dean's bottle-green eyes prompts Cas' stubbled jaw to snap shut on whatever he'd been about to growl, and he hands over the entire pack without further protest.
Even Bobby knows to shut his mouth and make himself scarce after Dean antagonizingly refers to his best friend as 'Cassandra'; granted, he'd stumbled in on Cas and Sam watching a rerun of some pathetically girly day-time soap opera, but that wasn't justification for belittling the former soldier of God's insatiable curiosity about human interpersonal relationships. Cas arches one dark eyebrow at Dean without moving from his lazy sprawl across Bobby's ratty sofa and replies, "One, fuck you, Dean. Two, you've made me watch exactly sixty-three episodes of that travesty of a medical drama with which you're so obsessed. Three, my name is Castiel Winchester and I have a dick." Dean's face can't seem to decide on an emotion on which to settle before he turns on his heel and goes to hide in the kitchen with Bobby.
"It's just a little ridiculous," Cas growls dangerously where he sits fuming in the back seat of the Impala, "That those arrogant, self-righteous blasphemers would extort money from the faithful under such erroneous pretenses!" Dean glances back at the angry draw of his friend's face in the rearview mirror before cutting his eyes back to the road. The last time that Dean had heard that same note of unbridled fury in Cas' crushed gravel baritone, the ex-angel had brought an archangel to his knees, and Dean takes that moment to add 'televangelists' to his mental list of 'Shit to Keep Cas Away From.'
Sam knows better than to speak into the tenuous silence inside the Impala. It feels like pulling the pin on a grenade and handing it off to an impatient toddler, or winding a guitar string over-taut and waiting for the inevitable crack when the tension dissipates like the snap of Gabriel's fingers into something equal parts shock and awe. In the backseat, Castiel groans in pain through unconsciousness, the sound heart-wrenchingly human, and Dean's eyes close briefly as he exhales slow and shaky before the Impala continues to devour the dark stretch of an empty Missouri highway with increasing voracity.
If Cas ever misses Heaven then he never mentions it aloud, but Bobby doesn't think that the man needs words to express the emptiness that his holy severance package has left behind. It's in the way he wastes hours of down-time reclined against the cracked and dirty windshield of the ancient Dodge pickup at the far end of the salvage yard, staring up at the blackbirds streaking through the clear South Dakota sky. It's in the way that he has to drag himself back into the house well past dusk and watch Dean laugh at his own crass jokes to chase the shadowed doubt from his bottomless eyes and decide that it was worth the emptiness after all.
It''s the rush of humid, warm air more than the shuffling of workboots over cheap carpet that pulls Dean from sleep, the loaded gun from under his pillow. It takes precious seconds for his eyes to adjust to the dark before he confirms Sam's gangly ass still lounged across the cot between the room's twin beds and Cas' empty mattress. The business end of Dean's Colt precedes him outside, but he immediately decocks it and tucks it into his waistband when he finds Cas leaned back against one of the Impala's wheels, arms curled around knees against his chest, talking quietly to the stars.
Cas trusts Sam with his awkward and often uncomfortable explanations of human behavior, even in situations that inspire an awful blush in the younger hunter's face and a painful stutter to his words. Cas trusts Bobby with his easy, gruff acceptance of another idiot hunter in the family and his unrefined, backwater wisdom. Cas trusts Deans with his very finite, very mortal life, but he draws the line rather adamantly when the older Winchester brandishes a pair of scissors and announces that the former angel is in desperate need of a haircut.
Dean comes back from a food run to find his little brother engrossed in an involved discussion of prime-time reality television to Cas. Rolling his eyes and chucking the paper bag of processed dinner onto the nearest bed, Dean catches phrases like 'psychological motivation' and 'overcoming phobias' while his gaze falls on the practiced motions of Cas' hands cleaning his gun. Sam is explaining the concept of a 'trust fall' when Cas' brilliant blue eyes wander up and lock onto Dean's, and then their resident ex-angel laughs so hard that he falls off of the bed in a graceless heap of jeans and gun parts.
Their latest hunt requires them to pose as law enforcement officers, lie convincingly when appropriate, and project an air of confident control at all times. After a day of arguing and thinly-veiled insults, Dean relents and accepts that leaving Cas behind in the motel might actually hinder their unorthodox investigation. Dean pauses outside the first victim's humble slice of suburbia to straighten Cas' forever-crooked tie, reminds him to hold his counterfeit badge right-side up this time, and barks out a laugh when Cas glares fit for smiting and punches him in the shoulder like he means it.
Holidays were never as particularly important to the Winchesters as anniversaries of family deaths, but Bobby still demands that they spend the most common ones—Christmas, Thanksgiving, the Fourth of July—in Sioux Falls. Cas doesn't necessarily understand why these specific days of the year are different than any other, and Sam doubts that he ever will, until Dean says that holidays are only important if you have family with which to share them. Cas stops arguing the exact date of the Lord's birth after that and develops an almost obsessive habit of announcing obscure international holidays every morning over breakfast.
The first time Sam rolls out of bed to find his brother and his brother's former guardian angel tangled together on Dean's bed, thankfully fully-clothed and dead-to-the-world asleep, he valiantly fights down the word 'cuddling' and coughs loudly to snap them both awake and apart. The second time occurs nearly a month later and involves an awkward conversation with his brother that Sam would really rather just never, ever fucking think about again, thanks. Cas is now convinced that he sleep walks and is not in control of his own body for six hours a night; Dean, to Sam's amused horror, has stopped requesting the foldaway cot for their double rooms.
Over time, Dean finds himself compiling two mental databases of things that Cas likes and loathes, and he updates each as necessary. Cas hates the cold, waking up before nine in the morning, dogs, televangelists, and Black Sabbath. Cas loves kids, classical literature, coffee, infomercials, and Dean.