Dean always knew that Sam would be the one to actually settle down. He's not gonna lie. He's happy for him, because Sammy deserves this, he deserves his wife and that little house with the white picket fence and a little girl on the way. He deserves it all, every single bit of it.
Of course Sam asked Dean to stay, to find a girl and move in down the street, but it was a lost cause. Because Dean was never going to have that life. He may have had it for a year, but it was never really meant for him.
It's a tearful goodbye as Dean moves on.
"You take care of yourself, Sammy. Make more babies. Bring home bacon, all that damn domestic stuff."
"And you gotta promise me that you'll be safe and come visit. I'm not having you disappear on me. And find someone to team up with every now and then. Don't hunt alone."
"You're gonna make a good father, Sammy. Just don't daddy me. I can handle myself."
There's one last hug and a passing, "Bitch," from Dean, followed by a "Jerk" to Dean's back. Sam watches as Dean slips into the Impala, and he's not even surprised to see Cas riding shotgun.
It's different than hunting with Sammy. It's hard at first, because Cas is still having nightmares of falling. But Dean's there to hold him, to comfort him with strong hands supporting him, and fingers brushing through Cas's unkempt hair.
Eventually they stop asking for twin rooms and things change a bit. There are showers taken together for the sake of time, which end with Dean between Cas's thighs. There are lazy kisses in the back of the Impala, the windows rolled down, letting the summer heat warm already hot skin. It's long nights on the road with their hands intertwined. It's crappy diner food and a milkshake with two straws. Glances while working a case and frantic groping against an alleyway, trying to make all these stolen hours count. It's off days spent in shitty motel beds, bodies intertwined, bruises and teeth marks on pale skin, fingerprints on hip bones, and kisses along stubble lined jaws.
It's not all fun and games though, there are times when they have to patch each other up. When needles threaded with dental floss puncture tender skin, as teeth grate and hands clench at bloodied bed sheets. But there are soothing words and soft touches and "kisses to make it better" while Dean laughs as Cas presses his lips to damaged skin.
It's day by day, hunt by hunt. It's lonely and painful, but they have each other, and Dean can find peace in Cas's arms. They see horrors that they didn't even know existed, but they deal with them and they carry on, because they find peace at the end of the night when they can let it all go for a few hours and just enjoy each other and this thing that they have been building during late nights with whispered words and hands dancing over clenched muscles and yielding flesh.
They go to visit Sam a couple years after that goodbye. The little girl is nearly three, and there's a boy on the way. Dean dotes on the girl, while Cas looks on. They exchange a secret glance, because they had a conversation recently about the fact that this is what they can never have. So they tell Sam to go on a date night with his wife and they watch the little girl and pretend that they will never have to leave. But then the morning comes and the road is calling, and the Impala's engine purrs as they drive away.
Sam's not surprised when he gets the call. He knew it was coming eventually, but it's still hard to hear the words.
"Sam, it's your brother. He's gone."
Sam takes the trip out to where it happened, and it's so strange to be driving a minivan instead of that Impala. There are toys in the trunk, no knives or guns, and some Disney CD is playing in place of AC/DC.
He arrives at the spot and steps out with shaky legs. He's prepared himself for this day, but it's still unreal. It's like he's in a bad dream as he walks past the banged up Impala to find where Dean and Cas took their final stand.
Their bodies are long gone, but there are stains. Cas's wing prints fan out over the ground, huge and magnificent. There's a gap in the print though, and Sam can tell it's from Dean's body, from where he held onto Cas as the light faded from his angel's eyes. Sam notices the blood in that spot and he can almost see the scene playing out. Cas going down and Dean fighting with his last breath. Them dying in each other's arms. Dean probably making some stupid comment on how "chick flick" the moment was and then Cas smiling before his face goes slack.
Sam wipes a stray tear from his eye. He can't afford to let himself mourn, not yet anyway. There are still things he has to take care of, like the Impala. He's gotta find a home for her, someone worthy enough. He can't take her, he can't have her sitting in the garage next to the bikes and the sleds. He's not going to burden his family with his past.
He makes his way over to her. She's been beat up pretty bad, but she's still gorgeous as ever. A small smile comes to his lips as he opens the door and slides into the familiar seat. He runs his fingers over the wheel, letting himself get lost in the memories for a few moments before turning his attention to what's new in the car.
The car smells different. There's a new musk to it and a scent that is definitely Cas, but it's mixed with his brother. Clothes are piled on the backseat, Cas's trench coat among them. There are papers sticking out of the glove box. Sam opens it and rifles through some of them. They're mostly notes for cases or receipts from burger joints, but one of them is in an envelope that's clearly marked "Sam" in Dean's messy handwriting.
Sam opens it gingerly and pulls out a piece of stained paper. He unfolds it and starts to read:
If you're reading this, Sammy, it's cause I'm dead as a damn doornail. Hopefully I went down swinging. I'm writing this for Cas, because he said that it would be good for me to have a will. Not like I've got anything of value, besides my baby of course. She's yours, Sam. If Cas is still kickin, he'll bring her round to your house for you. Just don't let her rust in some damn junkyard. And tell Cas that he's a dick. As far as I go, just throw me in some hole and torch my bones. The usual procedure. And if Cas happened to go out with me, toss him in too.
- Dean
Sam looks up and blinks away the tears that are clouding his vision. He doesn't know why, but he's laughing. He's smiling and laughing even though his brother is gone. But it's good, it's the only way he could have gone, and Sam knows that he and Cas are at peace, which is something that they've never had, but always deserved.
He puts the will in his pocket and finishes looking through the other odds and ends in the car. He finds things gathered from hunts, a claw here, some hair there, scattered among personal items. Sam has a feeling that the bottle full of what looks like lotion is most likely lube, and he's not sure whether to vomit or cry, because Dean and Cas had something, they had each other and they went down together.
It's when he finds the picture that the tears start to fall. It's a picture of Dean and Cas at Disneyland in full-on Mickey Mouse attire. Cas is even wearing the hat with the ears. Dean has an arm around Cas's shoulders, while Cas has both around Dean's middle, hugging him tightly. They're standing in front of the Haunted Mansion and Sam has never seen his brother smiling so big.
It's the first of a collection of photos. Most of them are blurry and candid. Dean asleep in a crappy motel bed, Cas grinning up at Dean from the backseat of the Impala, a shot of Dean and Cas messing around in the shower (Sam quickly goes past that one), Dean making faces at the camera, and a ton of pictures of Cas looking confused.
Sam sighs as he flips through them. This was the life that Dean had, it was good and he was happy, actually happy for once. The thought brings new tears to Sam's eyes because he didn't think that Dean would ever find happiness while hunting, and yet he did. He found it in Cas and Sam is offering up a prayer of thanks for that damn angel.
Sam puts the photos in the van, along with a video camera that is full of footage he's going to have to watch later. He packs up all of Dean and Cas's other things and tosses them into the van as well. Then he turns the key in the Impala and sits there, just listening to her purr.
It's strange to be making arrangements for the Impala, for her to be given to new ownership, for her not to have Dean behind the wheel and Cas next to him. He's going to have to thoroughly clean her after she gets back from the shop, which means prying the army man from the cup holder, and dislodging the Legos in the AC. He's not sure if he's going to be able to do it. It'll will be like taking away a part of his life, but he knows that he can't keep the car, and it was never really his anyway. It's still Dean's, even though he's gone.
After the car has been sold, Sam moves to the videos that he found. He plugs the camera into the TV after the kids have been put to bed and he has the house to himself. He sits back with a beer and watches as a fuzzy image of Cas appears on the screen.
"Is it on? Dean? Dean, is it working?"
Dean comes into view, and stares at the camera.
"Yeah. It's on."
Cas grins and points the camera at Dean.
"Get that out of my face."
Dean pushes the camera away and Sam can hear Cas sigh, then the camera is slowly tilting up to Dean again. It watches as Dean messes around on his laptop, oblivious to the fact that Cas is still filming. They are both in a hotel bed, and Dean's hair is a bit mussed. The camera goes back onto Cas who looks at it with his head tilted before it finds its way back to Dean.
Finally Dean looks up. He rolls his eyes and bats the camera down. It falls onto the sheet and Sam is stuck staring at a floral duvet while Cas complains.
"You probably broke it."
"I don't care. Why do you even have that damn thing?"
"Because I want to remember this, and you said that I could buy it."
"I didn't think you would use it to film me."
"What else am I supposed to film?"
"My ass."
"But that's still you, Dean."
Dean groans and the camera is picked up. Dean's face comes onscreen and he stares for a few minutes before his eyes go wide.
"Dammit, Cas! Give me some warning before you go south."
Cas appears, a smile on his lips and he kisses Dean. Sam averts his eyes as the camera films a long, languid kiss. He can hear Dean making that noise in the back of his throat and he fast forwards until he sees Cas's face again.
This time, Dean is filming.
"Say something, Cas. You're on your damn camera."
Cas grins and Dean groans.
"Stop smiling like an idiot."
"I love you too, Dean."
"You're a dick."
Cas lunges at the camera and it falls into Dean's lap where it films another passionate display of affection. Sam skips to the next video once Cas's shirt flies into the camera.
Sam sits there through hours of footage. There's everything from Cas filming Dean eating, to Dean saving an episode of Casa Erotica to the camera while commenting on everything that happens. There are several videos of Cas and Dean in Disneyland.
"We're here for a case."
"He's lying. Dean just wants to ride Space Mountain."
"Shut up."
It's nearly three am when Sam's wife comes down to tell him to go to bed. He points at the image of Dean and Cas making faces at the camera and speaks through the tears that are falling into his lap.
"How did these two morons even survive as long as they did?"
Sam doesn't finish the rest of the tapes. He files them away, planning to watch them in the future, but time gets away from him. His kids grow, and suddenly he's a grandparent. His son decides to study law, and Sam has to laugh when his boy comes home with the letter from Stanford. He's not prepared for the day that his son pulls the Impala into the driveway. He says he bought it off a friend and Sam has to hold back the tears, because she looks the same, perfectly preserved, still purring away.
Sam doesn't know what to do when his son finds the videos.
"Is this Uncle Dean?"
"Yeah."
"Who's the messy haired guy with the blue eyes?"
"That's Cas."
"Was he an angel?"
They finally have the conversation that Sam hoped to avoid. But his son deserves to know, to know about Sam and Dean's past, about the angel that landed into their laps, about the fact that Cas fell because of Dean, and how they remained together till the end.
Sam takes deep breath and then he tells the story of two brothers, a fallen angel, and the '67 Chevy Impala that they called home.