Work Text:
The first thing Cas says when they walk down the bunker's stairs and find him sitting on the table, waiting for them is, "Dean," and the expression on his face is horrified as he looks at Sam's brother, "What have you done to yourself?"
Sam jerks to stare at Dean, while his brother looks slightly taken aback, "What?"
"There's...a taint." Cas makes a few steps towards Dean and stops, and seems for all the world like he would rather back away than come closer, "What happened?"
Dean does a little eye-roll, like he doesn't understand why anyone would raise such a fuss. "You need to get your batteries checked, Cas. Engine light's coming on but nobody's home, you know what I'm saying?"
Sam is very good at resisting the urge to throttle his brother. "Dean, he probably means the Mark." And again, Dean has this flicker of an expression, exasperation mixed with amusement and so, so much fatigue.
"What Mark?" Cas glances between them. The naked concern on his face at least gets Dean to own up to the truth.
Dean rolls his sleeve up, swallowing before he says, "Cain's gift to me."
Castiel's face when he sees the mark on Dean's arm makes Sam's hair stand on end. Sam looks at Dean and he can't see anything different, but Cas's expression is not lying. Something is wrong. Sam hadn't liked the Mark from the moment he laid eyes on it, but it's been shelved, forgotten as they worked the case in Wisconsin and then Illinois. Dean was a master of deflection and Sam was still angry enough to let him get away with it. Now, Sam thinks he should have pressed the issue.
When he looks at Cas, the angel is still staring at the mark, and his eyes are wide. Even Dean is unable to ignore his reaction. "What is it, Cas?"
"That Mark is a curse."
Dean gives a small amused exhalation of air, "I expected nothing less." He asks honestly, "Do you know what any of it means?"
Cas finally lifts his eyes from the blemish on Dean's skin to look the man in the eyes. "You took the mark without knowing what it means?" And wow, Sam had forgotten Castiel could growl like that. The angel steps closer to Dean, and his lips are pressed together in a tight line. Sam watches them both, trying to figure out exactly how much trouble they are all in.
Dean has his game face on. "It means I can ice Abaddon. Forever. That's good enough for me."
"Dean," Cas starts, frustrated, but is interrupted by the sudden ringing of Dean's phone. The bunker has enough of an echo that Sam can hear across the line, two simple words that fill him with dread, "Hello, darling."
Crowley had promised to deliver the blade, as Dean explained to Sam in quick bullet points. The First Blade plus Cain's Mark equals dead Abaddon. And Crowley doesn't break his word.
Cas goes with them when they leave to meet the King of Hell. Sam knows how he feels: he is certainly not letting Dean go through with this alone. In the time that they've been apart, a mere two weeks, Dean had managed to deal with Crowley and a part of Sam will never forgive himself for that. He knows where all such deals always end up. He also knows it was Dean's choice.
When they are at the meeting spot, they idle, waiting for the demon. Dean watches the horizon, Sam checks his phone as they both lean against the car's hood more out of habit than any real desire to be close to each other. Dean's been awfully quiet, and Sam wishes it didn't gnaw on him. The anger's still there, but he's been at Dean's side for so long that he notices everything, he notices the resigned air around Dean and it's part of the reason he can't leave Dean alone. Cas is also quiet and thoughtful, leaning against the side of the Impala, staring at his own hands. He's been like that ever since they left the bunker, and Sam worries about him too.
"Hello, boys."
Sam and Dean whirl to find the King of Hell behind them, holding a thin wrapped box in one hand. "I come bearing gifts," he smiles.
Castiel makes an abortive movement towards Crowley, but Dean shoots him this glare, like he can tell how much Cas wants to hurt the demon, and he is telling him with just a look to shelve it, no alternatives. The surprising part is that it works, although Castiel now looks even angrier and Sam can bet it's not only directed at Crowley anymore. But hey, Dean's ability to piss people off is legendary.
"Oh Castiel, I didn't see you there," Crowley says, standing directly opposite the angel, with the Impala the only thing between them. His eyes slide past Cas and lock onto Dean. He wriggles the package in his arm a little. "Well?"
Dean rolls his eyes again, and grabs the box out of his hand, immediately tearing at the red bow and wrapping.
"You are welcome," Crowley's watching him unwrapping the gift, like it's fascinating to see Dean's fingers undoing all that careful work. Dean pulls the "blade" out of the black box, and it's simply a curved jagged bone. Nothing like the one they slew Dick Roman with, this one is slick, dark and sharp, like it's been pulled out of a large bird's wing.
"Of course, you had something to do with this." Castiel says, staring like he would like to flay Crowley with his eyes alone. Sam supposes he probably could.
"Yes, yes," Crowley looks up, and his eyebrows lift up. "Why Cas, you look upset. Shouldn't you be sending me flowers?"
Sam frowns. Castiel appears stunned for a second, but his expression quickly changes to bitterness. "For letting Dean be marked?"
"Well, yes." Crowley chuckles. "After all, I know exactly what that means. And you always had the brains to figure things out on the fly."
"Hold it, you two," Dean is pissed, "Nobody let me do anything. It was my choice, Cas." He glances at the angel, but too quickly looks away. "And you," he points the bone at Crowley, "Do you know how to find Abaddon?"
"Must I do all the work?" Crowley snarls, "You find her." He throws one last glance at the angel, "You are welcome." and he is gone into thin air.
Sam looks at Cas and no, he is not letting this slide anymore. "Cas, what did Crowley mean? What does the Mark do?"
Cas's tone is grave. "A curse was placed upon Cain, that if someone did something to harm him, the damage would come back sevenfold."
"And that means...?" Sam is not satisfied, he had found as much in all the books, but nothing more specific. "That lightning will strike down anyone who tries to harm Dean? God smites them? What?"
"No, I..." Castiel hesitates like he isn't sure how much he should say, "I've only heard of what the curse of Cain was, I don't know for certain." In Sam's opinion that's the shifty look on Cas, and he wants to call the angel on it, but Cas looks so miserable all of a sudden that Sam can't. Sam trades a look with Dean, a habit that he can't break no matter how much bad water is between them. Dean shrugs, like nothing bothers him.
"Well that's terrific," Dean lays it on thick. "Now I'm done discussing our body-art, can we focus on the real problem here? How do we find Abaddon?"
And so he deflects again, and Sam lets him. He doesn't know how much longer he can do this.
***
Sam doesn't forget the conversation. He spends the evening lying on his bed, scouring the internet for any information he can find on what a curse of Cain is, but all he comes up with are weird tales of Cain wondering the earth from the dawn of time, causing havoc. None of it tells him anything of practical use. But Dean doesn't appear to be sick, and if he looks tired then it's the job, nothing physical. So Sam thinks, they have a bit of time to figure it out. Shutting his laptop, he walks out of his room, quietly closing the door behind him and intending on dinner when he hears voices from the main room. Dean and Cas are sitting at the table, on the opposite sides, two opened bottles of beer between them. Sam comes closer and hears:
"Cursed, huh?" Dean takes a swig out of his bottle. "Wasn't I always?" He smiles at the man across.
"It's not funny," Cas says, with a flinty look. He's not touching his beer, and Sam's not surprised. If PB&Js taste overwhelming, he doesn't want to know what alcohol tastes like. Cas doesn't sound angry anymore and his eyes, when they settle on Dean, are pained. "You really should be more careful."
"Why?" Dean says. "I know, you think I don't understand the risks but man, I went with my gut. The last thing we need now is Crowley and Abaddon nuking it out all over the continent."
"You always 'go with your gut'," Cas says, "You go with your heart. I wish you'd think things through."
"That's what we've got Sammy for, right?" Dean winks, and takes another swig. Sam finds his blasé attitude annoying. He is about to walk in and announce his presence, when the air in the room changes. "What did Crowley mean when he said 'you are welcome', Cas?" Dean says it slowly, deliberately, and his eyes never leave Castiel's face.
Cas' eyes flicker off to the side, uncomfortable. "He was being Crowley. It's nothing."
Dean doesn't move a muscle. "Right. Well, if you want to continue, please be my guest. God knows, lying to each other never hurt anything." His lips twitch in a bitter smile. Across from him, Castiel's shoulders jerk a little. Sam suppresses a sigh. The lies is what hurt the most. He never wanted to die, but he would rather be dead than have his brother trick him, and that's their problem. Right now, he doesn't know how to fix it, so he stays still, quiet in the alcove of the room.
"Dean," Cas gathers himself, like it's a feat of strength, and looks at the man again. "I wish you hadn't taken the Mark."
"I get that. And...?"
Sam leans against the door, all his muscles tensed. Maybe he'll finally hear some truth.
"And if what I know is true, the curse of Cain is to wander the Earth for all time."
Dean starts. "What, like--"
"Forever." Castiel watches Dean absorb that.
"You're saying..."
"I'm saying, that the curse is immortality." Cas swallows, "And if that's the case, you will never have peace Dean. Because you cannot die."
"Wow." Dean lifts both eyebrows, staring at his arm where under the sleeve the mark burns bright red. He looks like he can't recognize his own limb, "Huh."
"You should have thought of the consequences before you took it, Dean!" Castiel suddenly takes off from his chair, the scraping noise it makes echoing loudly across the room. He runs a hand through his hair, a human gesture left over from his past experience. He is an angel again, sure, but he's changed.
"Immortality... well, it could be worse?" Dean says, thoughtful. He's not looking at where Cas is pacing the floor across from him, he's staring at his arm, a strange expression on his face. Not happy, not sad. Sam's mind is reeling with implications and Dean simply...accepts it. Just like that. "Although it will suck to be stuck in a wheelchair when I hit triple digits."
"You won't age, Dean." Castiel whirls at him, suddenly realizing that Dean hasn't inferred it all. "You will wander the Earth, unable to die, never welcome in Heaven, for millennia. All the pain, all the suffering you will witness, and no rest."
Dean lifts his eyes, a slow realization starting on his face, staring at Cas for something that feels like eternity. "Is that why...?"
Cas stops and suddenly it's as though he is relieved that Dean understands. He presses out a strangely nervous, "Yes." He looks vulnerable as he stands there in the middle of the bunker, with Dean's gaze fixing him in place so he can't flee. For a moment, he looks like he wants to.
Sam thinks he is missing something, so he leans forward trying to discern from the expression on his brother and his friend's faces what they meant.
Dean and Cas are both silent, but it's like they are both thinking the exact same thing and they don't need words. Eventually, Dean clears his throat and looks away, some distant embarrassment flickering over his features. Castiel stays gazing at him with searching, almost desperate eyes.
After a while, Dean says, his voice quiet. "Do you think I will forget things, eventually?"
"I don't know," Cas is also quiet, and his expression fades into something more normal, polite. His voice is kind, "I don't know how human memory works over a lifespan of eternity."
"You know, that is what scares me the most about the idea. That maybe I'll live long enough that I'll forget. Who I was. Who Sam was."
At his place in the alcove of the door, Sam flinches.
"I don't know. I'm sorry, Dean." Cas breathes out slowly, a shaky drawn out breath, like gathering courage. He wears his heart on his sleeve. "But I do know, that no matter how much time passes, I will never forget who you and Sam were. I know that much."
"Guess you'll have to remind me."