It was the worst idea ever, because look how it turned out for Charlie, but they were desperate.
Now there's a version of Dean downstairs that's all the Mark of Cain, just anger and bloodlust and not much else, and upstairs there's Dean, and he feels something like himself again, with the guilt but no urge to drink until it fades.
Okay, so yeah, the urge is there, because that's what he's always done, except that he can't, because Sam's looking at him like he used to, the fear isn't there, he saves that for the one downstairs.
Dean just wants to savor that, the fact that Sam isn't afraid of what he'll do anymore.
He can't hunt, and he doesn't want to. They talk about Sam taking the downstairs one out, if there was something bad enough to warrant it, but Dean doesn't even want to hold a gun these days.
"Don't go down there," Dean begs, cooks with kale and something called quinoa and Sam stays upstairs and smiles at him a lot.
Dean makes greasy bacon cheeseburgers and takes them downstairs.
When he looks in the mirror and when he looks at his other self, they might have been dragged in from different points on his timeline, but no angels have had a hand in this. The anger and the self-hatred sits on his face like a good ten years, and on a bad day it's more like twenty.
It's a good day today. Downstairs Dean sits at a table carving Enochian symbols into the wood with a butter knife he must have pocketed after breakfast, and the Mark on his arm is quiet.
"Nice," Dean says, as he slides one plate across the table, and puts another on his side. He pulls out a chair, and as he sinks into it, their eyes meet.
"Beer," Downstairs Dean accuses.
"It's lunch," Dean says.
They eat in silence, but for the sounds of appreciation from them both, that, at least, still the same.
He's not suicidal. Never was, really, so Dean can be down here and not have to worry that he's going to end up with a butter knife in his eye or his own hands choking the life out of him.
The last time Sam came down it was a bad day, though, and downstairs Dean stabbed him with a pencil and upstairs Dean held a gun to his own head just to get his brother out of there alive.
It was his idea. Dean's. Both of them, because they were still one person then, so Downstairs Dean doesn't complain as much as upstairs Dean keeps expecting him to. He couldn't help it when he hurt Sam. It was the Mark. Dean knows that better than anyone.
This way, Dean can almost pretend that Sam might forget he's down here, that this part of him exists at all.
Downstairs licks the plate clean, and Dean grimaces, slightly disgusted. Downstairs grins. Dean grabs the plate and tries to leave, but Downstairs grabs him by the wrist.
The plates fall and smash on the floor.
"Not again, man, jesus," Dean says, and he's not talking about the plates. He tries to pull out of Downstairs Dean's grip, but he doesn't try as hard as he probably should.
He's not scared like he was the first time it happened. And he kinda gets it, because he's been downstairs, alone but for one visitor for weeks, and he remembers how part of him got antsy when it'd been a while, and for his other self it must be so much worse.
But he's never been shy, either, and if he wanted something, he always went for it, and so he can't blame his other self at all. Not really. And it's another reason for keeping Sam upstairs, for not letting him down here, because this is the part of Dean with very few scruples.
If anything, he owes this to himself, so he quits struggling, and he lets Downstairs Dean pull him into his arms. "No weird shit," he reminds him, and, "no rough stuff, either, okay?"
Downstairs chuckles and presses his lips to the back of Dean's neck, hands already pulling Dean's shirt off his shoulders.
Soon he's shivering, because it's cold down here, and his clothes are scattered around his feet, and he's muttering, "I said, no weird shit," but he doesn't stop his other self from thrusting his tongue up his ass.
"I'm going to fuck myself," Downstairs Dean says between licks. "What's weirder than that?"
And Dean has to concede. Except, "Bed," he says, because it'll be warmer, and he's still afraid that Sam will come down and see them together like this.
But Downstairs Dean yanks him to the floor, and his knees hit hard, and his palms burn with the impact, and the sound of a zipper seems to echo off the walls and then there's the hot, wet nudge of a cock at his hole and it drives home in the space of one breath and fire spreads over his skin.
He cries out, but there's a hand over his mouth, muffling the sound. "Can't have Sammy coming down," the man behind him says, and jerks his hips, driving his cock deeper. "I wanna take my time."
"You're an asshole," Dean gasps, and Downstairs just chuckles, the tone of it saying 'well, duh' more than words ever could.
Pain fades into pleasure, and Dean gets hard. Even this part of him doesn't think sex is anything to be ashamed of, and he had always been curious. So what if he likes it, and it keeps Downstairs Dean quiet, there's really no downside.
If anything bothers Dean, it's the fact that despite the claim that he wants to take his time, Downstairs Dean is impatient.
And more than a little competitive.
"Wait for me, you bastard," Dean says, as the man behind him starts to lose rhythm, starts to breathe harder. Dean strokes his cock, hard and fast, because his other self is...selfish.
"Gonna miss this ass when this is over," Downstairs grunts, twisting his fingers into Dean's butt cheek as he snaps his hips. "When they stick us back together, what you gonna do, gonna miss being my bitch?"
Dean rolls his eyes and clamps down hard on the cock inside him. Pulls a grunt out of his other self, and his hips stutter, jerk, and still, buried deep.
There's a pulse inside him, and it's like a heartbeat, and everything goes slick and wet, and Dean's orgasm hits, riding the wave, and it's almost like they're one person again.
Until it subsides, and Downstairs Dean shoves him away and stumbles back, throws himself on the bed and starts snoring.
"Jerk," Dean mutters, as he picks himself up, straightens his clothes, and heads back upstairs.