"Yes. You hear me?" Dean asked, looking up above, at the inky darkness reaching out for him, wanting him even though it'd already taken everything that mattered to him. "Yes."

He hadn't been able to say it before, hadn't even needed to. But now, Cas was out there, past that darkness, and he was alone, and Dean... God, he couldn't even fathom that: Castiel alone, thinking he wasn't loved.

The Empty had taken Castiel's body, had taken everything. Now it was Dean's turn to give.

Sam and Jack were in there, fighting that thing tooth and nail, and soon, the dark pulled Dean in as well.

"Cas!" Dean cried. "Cas!"

Where was he? Where was he?

Somewhere. Has to be somewhere, Dean thought.

Sam was screaming, a fierce battle cry as he fought whatever horrors this dealt him, as he fought for his best friend, his brother. Jack was crying out, and Dean could hear the deep, warbling note of Jack's powers in the air, trying, trying...

"Come on, Cas," Dean begged. "I came here for you." Black pulled at him, tore, ripped at his clothes, felt along till it crawled underneath his skin. It tried to go in his throat, to steal the one thing he had left. "Cas, you deserve to be saved, you son of a bitch!"

All around them, a scream shrieked that made Dean bled - from his eyes, his ears, his nose. Humans weren't meant to hear it. The scream became a word, a long-drawn out, agonizing word: SSSLLLEEEEEEPPP

"No!" Dean cried. "No, it ain't gonna happen."

A hand found Dean's.

"Cas?"

"Dean!"

The darkness tried to eat Dean, and it tried to pull Castiel back into it.

Dean held on. Cas held on. A face became apparent through the dark, the face that Dean knew and loved. Tears lined Castiel's eyes.

"You just gotta hold on, okay?" Dean said. "Just hold on."

"I trust you."

The blackness writhed and squeezed, as if it would implode.

"Jack!" Dean cried, warning his kid.

They fought. Oh god, they fought.

Gold obliterated everything.

Dean was left kneeling on the floor, his family around him, Castiel a pure light above him.

"You need a body," Dean reasoned. "And I can give you one."

His family didn't object, as he held his arms open, as he readied himself for this, as he was ready to become the one thing that would get them all home safe:

"Yes."

Blinding light, and pure, beautiful, loving energy filled Dean up, till Dean was no longer Dean, till he was Castiel, till Castiel was Dean.

Dean and Castiel became one. They fused together. They loved.

They opened their eyes, and they glowed blue.