It's cold as a priest's balls in the car and Dean's too drunk to safely drive back to the motel. Unfortunately it was laundry day earlier, and even the emergency bags of clothes are sitting pretty in the room along with a probably snoring Sam.
Dean digs around ineffectually for a good few minutes before his fingers wrap around the coat. It's the one thing that's consistently in every car they use these days, folded neatly in the trunk, or sometime in the backseat if there's no room among all the gear. Sam hasn't mentioned it, if he's even noticed. He's got a lot on his mind. They both have.
It's not a warm coat, but it's long and it's an extra layer, so Dean fumbles it over himself in the best approximation of a blanket he can manage and curls up into the seat to try to get some shuteye.
Waking up, his hangover-heightened sense of smell picks up the coat before anything else.
It smells of Cas. Or maybe Jimmy, maybe angels don't have their own smell. Dean kinda hates that he doesn't know. Either way it's a damn painful way to wake up and cuts through his hangover like a rusty knife. If he wasn't going to throw up before then he sure as hell will now.
The coat is neatly folded in the backseat before he even exits the car, heaving into the bushes lining the quiet road where he'd parked.
The next time isn't so incidental. He and Sam had a yelling match again, and Dean doesn't even remember what it was over. They do that a lot these days, and it's a safe bet that Sam got sick of the dark cloud hanging around Dean and tried to make him talk about it or stop drinking so much or out and out told him to stop wallowing. So Dean's on his own heading to interview witnesses for the case they're on while Sam's headed over to the morgue, choosing to deal with the corpses alone over dealing with Dean.
Understandable. Dean would opt out of dealing with himself if he could.
His eyes catch on the tan fabric in the rearview as he checks his hair and the bags under his eyes, and he stares at it for a long moment. When he gets out of the car, he brings the coat with him and shrugs it on. He's not sure why, only that he didn't feel like going in and talking to grieving widows alone, and somehow the idea of wearing Cas' coat makes him feel a little like Cas is with him, about to tell the shaken civilians all about the monsters in that awkward, matter of fact way of his.
It's back in its place in the car before he goes to pick up Sam, but it becomes a habit to put it on when he and Sam have split up. A part of his Fed get up that he's careful not to let Sam see.
Eventually it stops smelling like Cas, or Jimmy or whatever, and that stings just as much as recognising the smell had in the first place. But it still feels like it brings a little bit of him back whenever he catches himself in a reflection, trenchcoat filled out and alive around him instead of passive and neglected in the car. It doesn't fit quite right, and it's not as warm as some of his own jackets, but it feels comfortable in a way even his dad's old jacket never did.
Sometimes he takes it out and doesn't wear it, instead draping it over a chairback as if Cas left it there himself and will be back any minute to reclaim it. It's pathetic, but that doesn't stop him. He is pathetic these days, there's no point in denying it.
Sam's getting worse and Dean can't leave him alone as much, so the coat stays safely in the trunk, untouched for weeks at a time. He's still careful to bring it with them whenever they switch vehicles, and he nearly has a heart attack when he goes to look for it and Sam's moved it to get to something else. When he finds it again he spends way too long with it in his hands, resisting the urge to pillow his face on it.
A week later, he takes Sam to the hospital. Leaves him there. There's a miracle guy Dean's got to go find, but if he's honest with himself, he doesn't think there are any more miracles left out there for them. They've used up their allotted and then some.
He stops on the way and goes to a bar. He wears the trenchcoat over his plaid and tries not to feel self conscious about it as he pushes through to order his drink. Some drunk splashes beer on the sleeve and Dean almost punches him out then and there, mostly stopped by the brewing panic over whether the liquid will stain and whether there's anything he can do to stop it.
It probably won't, it'll probably dry up fine, then come out in a regular wash. The damn thing's supposed to be dry cleaned, but Dean's pretty sure it could survive. He rushes to the men's room all the same and blots at it with tissues and tap water until his arm is soaked and he can't tell where the original area of the spill was.
Dean breathes and forces his eyes up to his reflection in the grimy bathroom mirror. The tan around his shoulders settles him enough to stand straight. One drink and then he'll get the hell out of here and back on to helping Sam. Trying to help Sam. Failing to help Sam.
Emmanuel's house is very neat looking. Tidy and normal and safe. Dean hates it on sight and only hates it harder when he finally meets the miracle man.
It's Cas. Alive and whole, freaking unscathed apart from his apparent amnesia. Living with some chick who found him naked by the lake (where Dean would have found him if he'd just stayed longer. If he'd just looked) and convinced him to marry her. She seems nice enough, kind enough. Dean hates her more than he hates the house. More than he hates the ugly blue sweater she's dressed Cas in.
He gives Cas the trenchcoat back at the hospital and only feels a twinge of grief.
He leaves Cas catatonic in Sam's place, and then he goes and gets him again, then they explode Dick, and they wind up Purgatory. It's a lot less fun than the one in Miami.
Cas leaves again, and Dean would scream at him if he could, yell at him to stop leaving all the goddamn time and stay to fix his mess. To fix Dean. By the time they find Cas again, him and Benny that is, he's saner than he's been in months. Scruffy and dirty and nothing like himself, no angelic dry cleaning keeping him pristine. Dean tells himself he doesn't care. Hell, the peach fuzz really does suit him, or would if Dean could let go of his mental image of him.
Dean rests on the forest floor as close to Cas as he can get away with without getting a raised eyebrow from Benny. He doesn't mean to fall asleep, though god knows he needs it, every moment of Purgatory existing in that same dingy glow of light and danger as they trudge endlessly onwards, but he's only human. He thinks.
Cas has moves away by the time he wakes up, but there's tan fabric covering Dean, and it smells like Cas again. Albeit a mucker, more mulch covered Cas. It halts the panic building in Dean's throat as he glances around wildly for any sign of where Cas has got to. Somehow the idea that Cas would leave the trenchcoat behind doesn't occur to him, seems far less likely than leaving Dean himself, and sure enough Cas comes back to collect it within minutes of Dean waking. Dean doesn't mention it, and he doesn't ask Cas to stop when he does it the next time Dean falls asleep. There are no nice ways to wake up in Purgatory, but it comes as close as anything could.
They get out. Him and Benny. Not Cas.
Dean sees flashes of tan every time he wakes up. Sees it out of the corner of his eye. Sees it, just for a second, over his own shoulders sometimes when he catches his reflection. Then he sees it everywhere.
After everything. After ugly blue sweaters and hospital clothes and coverings of bees and Purgatory grime and... everything, Cas showers and puts on a suit jacket and a blue tie and the trenchcoat over the top, and Dean nearly chokes on his tongue at how gorgeous he looks. How he looks like Cas again.