As the cloud rolls across the earth and swallows up the car, all Dean can think is this: They're going to die.

He takes his foot off the gas. Pulls the keys from the ignition, and opens his hand, just lets them fall to the floor.

Sam keeps saying his name. Dean. Dean. Dean. Over and over, urgent, begging him to do something, anything.

So many years have passed since Dean needed to be responsible for Sam, since he actually had to look out for him. Forget all the fucked up things Sam has done—because Dean's done stuff too. Forget all that, because Sam's been a grown-up for a long time, and Dean's responsibility really ended the day Sam walked out the door and left for Stanford.

And yet, now, when there's nothing they can do, nothing Dean can do, Sam's looking to him, and he's scared.

His fingers claw at the seats, scarring the leather. Dean would smack him for that on any other day, but he just shakes his head. "It's over," he says, and his voice is barely audible over the roaring outside. "We're done."

Sam's face goes blank, the terror and the panic just slides right off, and when his lips form the word 'no', tears slip down his cheeks and his lips start to quiver. "No," he says, a little louder. "No." He turns his head, like he's looking back toward the bar, but there's nothing outside but swirling black smoke. "We just..."

"Got out alive," Dean whispers. "I know." There's smoke seeping in through the chinks and gaps in the doors. It's coming up through the dash. Dean coughs as it enters his lungs, and it tastes like death and decay. He reaches out, and he cups Sam's cheek in his hand, wipes away a tear with the pad of his thumb. "But I can feel it, Sam. This is the end of the road." He coughs again, chokes as his airways thicken.

Sam starts to cough, too. His fists twist into the front of Dean's shirt, and he pulls him close. "I love you, Dean," he rasps, and turns his head away as his lungs bring up black gunk that clings to his lips like oil. "You know that, right?"

"Yeah, Sammy." Dean wipes black crap off his own lips with the back of his hand. "Hey, little brother." He can almost feel his lungs collapsing inside his own chest, and it hurts. "We're not coming back this time." He's not afraid. Maybe he should be, but he's not. The swirling smoke that fills him, it burns like sucking on a blow torch, but there's only relief. They can finally throw up the white flag and surrender, and they can do it together, and it feels right, somehow.

Sam starts to crumple, like he can't hold himself upright any more. Whatever is choking him is running down his chin now, and with each cough, a fresh flood of it spills out. "Not letting go," he chokes, more bubbling up out of him as he collapses forward into Dean's arms. "Wherever we end up, I'm not letting you go."

Sam spasms one last time, coughs and soaks Dean's shirt. The inside of the car is full of the smoke, so black that Dean can't see past Sam in his arms. He sees the moment Sam goes still and he doesn't care where he's going, just as long as Sam's there waiting for him.

fin