Chapter Text
The Empty comes on slow.
Cas could feel it niggling at the periphery of his mind’s eye, tendrils of electric current in the air, could feel it like animals can feel a storm coming. It’s all the heaviness of oncoming rain, all the portents of the inevitable.
He knew, from the moment Dean said it, from the moment he gave name to the love that Cas has long since acknowledged, that it was only a matter of time.
But there was still Chuck, still the threat of harm to Jack, still the loss of Dean’s temporary copied soul. Cas could hold those things in concert with his love, could dampen his own joy whenever Dean looked at him with that open affection in his eyes.
It wasn’t as if their lives had fundamentally changed. Dean touched Cas more freely, looked at him more often, even put an arm around him in front of Sam, but they had so little time to themselves. Even on the nights that Cas could spare to stay with Dean - to watch over him the way he has always, always wanted to - even with Dean curled into him, wrapped around him warm and possessive, Cas could pull up thoughts of the Empty itself.
He knew he should tell Dean, knew it would only make it worse, if his moment of happiness came when they finally thought they were at peace. But Cas couldn’t bring himself to take that small measure of happiness from Dean, too. Couldn’t bear the thought of the way he would retreat, the way he would look at Cas with that age old burden of responsibility. The way Dean would twist it on himself, if he knew that he was the one thing that could give Cas a moment of true happiness; the one thing that could take Cas away from him again, for good.
It comes on slow, by increments, in degrees, building like a pressure in the back of Cas’ skull, but it comes.
And now they’re here, in this windowless room, the useless devil’s trap, the temporary safeguard of a bloody sigil the only thing keeping Death out. Billie pounds on the door, and Cas knows it’s only a matter of time.
Dean is apologizing already - “I’m sorry, Cas. She’ll kill you and me both. I’m sorry” - and Cas’ mind is running through scenarios, disregarding them, the old commander of a Heavenly Host still trying to work out a strategy.
In the end, it is easy.
Billie pounds on the door, and the Empty pounds at Cas’ temples, the tightly furled happiness in his chest already wriggling out of its spiral to spread like the fronds of ferns growing under the sun.
In the end, Cas looks at Dean, this man who would give himself to the world, so burdened by despair, but still beautiful. Still Dean Winchester. Cas looks at him and smiles.
“When Jack was dying,” Cas begins. “I made a deal with the Empty…”
He tells Dean about the deal, about the conditions, and watches Dean’s bemused confusion as they stare at each other.
“I always wondered, ever since I took that burden, that curse, I wondered what it could be?” Cas says. “What my true happiness could even look like.”
Dean is getting it, and he’s frozen. Cas can recognize the frantic realization in his eyes, even as his expression closes off.
“And it could have been any moment in which you let yourself love me, Dean. Because the one thing I want, the thing I’ve always wanted, was you. But I think I know… I think I know now. The only thing that I have wanted more than to love you, to even dream of being loved by you…” Cas takes a deep breath. He’s smiling. The sharp pain in his chest is like sunlight breaking through - blinding and beautiful.
It’s what he told Dean once, the twenty-six year-old Dean who accompanied him to Turkey: Human love is unbearable. It’s all that there is.
“I know... I know how you see yourself, Dean. You see yourself the same way our enemies see you. You're destructive, and you're angry, and you're broken. You're ‘daddy's blunt instrument.’” Cas watches the muted emotions on Dean’s face, the way he shuts himself away from it, even in his guilty certainty of his own image.
“And you think that hate and anger, that's... That's what drives you, that's who you are. It's not. And everyone who knows you sees it. Everything you have ever done, the good and the bad, you have done for love.” Cas’ eyes are prickling - that very human sensation, this thing that he learned from Dean too.
“You raised your little brother for love. You fought for this whole world for love. That is who you are . You're the most caring man on Earth. You are the most selfless, loving human being I will ever know.” Cas smiles through his tears, crying now. Dean is staring at him, looking at Cas like every word is a knife.
“You know, ever since we met, ever since I pulled you out of Hell... Knowing you has changed me. Because you cared, I cared. I cared about you. I cared about Sam, I cared about Jack... I cared about the whole world because of you.” Cas chokes a little. Perhaps it is not so easy. It is all so bright and blinding, and he is bursting with it, with this feeling, with what’s coming.
“You changed me, Dean.”
Dean’s blank expression cracks a little. His voice is low, and Cas can read him, knows that it’s fear there. “Why does this sound like a goodbye?”
Cas takes a breath, one of his last, and puts one hand on Dean’s shoulder where he knows the mark of his first touch is seared into Dean’s skin. Cas’ other hand cups Dean’s cheek and he smiles up at him. “Because it is. Forgive me, Dean.”
Cas kisses him, kisses the way he always has, the only way he knows how, like it will be their last. With the last bit of grace that he still possesses, that spark at the very center of him that is not so unlike a human soul, Cas pushes the last bit of power he has left into Dean. It isn’t enough to stop Billie, not even enough to transport them out of this room, not enough to heal, not enough to save them on its own. But it is enough, just enough, for Cas to open up his grace to Dean, to force onto him the truth and depth of Cas’ feelings.
Dean gasps against his mouth, light pooling between their lips, along Cas’ hands, pouring into Dean, forcing him to see.
It is cruel, in its way, Cas knows this. He feels Dean’s shudder, feels the tears that slip down Dean’s cheek, hears his muffled little sob against Cas’ mouth as it hits him.
For this one moment, Dean sees himself the way that Cas does.
For a moment, just one fleeting moment, Dean Winchester, the abandoned boy, the wayward righteous man, the man who carries the weight of the world on his shoulders, knows - cannot help but know - that he is loved. Loved, right down to the center of him, clear through to his soul. Loved in a way that asks nothing in return. Loved as he is, not for the chance to change him or use him.
“I love you, Dean,” Cas murmurs. “Always and forever.”
“Cas,” Dean chokes out, scrabbling at his coat, his hands shaking. There are tears on his face. His eyes are wide and wild. So bright, blinding, beautiful. “Don’t do this. You can’t do this.”
But the Empty is coming. Cas can feel it pulling towards him, hears it as it squelches through the bunker’s walls.
Dean hears it too and turns to glance behind him at the blackness, just as the door bursts open. Billie stands on the threshold, and the Empty comes.
“Cas,” Dean says, turning back to him, despair and desperation in every line of his body.
Cas can barely speak around this feeling. One perfect moment of happiness, to know that Dean understood, however fleetingly, his own worth. It is not quite extinguished by the following devastation. Cas cannot regret it. He can never regret the things he does to save this man.
“Goodbye, Dean,” Cas says, smiling for the last time into the face of the man he loves. He shoves Dean roughly away, throwing him at the wall.
Billie steps into the room.
The Empty comes.
It is all there is.