When he first went outside he quietly called out "Cas? Cas, I really need you here." He waited. Nothing. He tried again- louder this time. Nothing. "Damn it Cas! I really need your help!" Still nothing.

Castiel heard him. He heard his silent plea before he even opened his mouth. But he couldn't go to him. He had his orders, but he didn't know how he could face him. How he could look into Dean's eyes and maintain his composure. He waited. Tried convincing himself that maybe Dean would give up. He knew he wouldn't though. His love for his brother and his faith would keep him going. Not faith in God or angels but faith in Cas. The guilt was a noose slipping tighter on Castiel's neck.

"Goddamn it you stupid sonofabitch!" Now he's largely just shouting expletives and insults. At least it's cathartic for him...and it drowns out Sam's screaming. Cas wishes he could help Sam somehow. He asked to be allowed to put him to sleep- they are going to release him anyway once Bobby and Dean fall asleep- why make them all suffer in the meantime? It did not go over well. He tries to stop thinking about it. About what is to come.

Dean falls silent. He paces back and forth. The desperation rolls off him in waves. Castiel can feel his charge's heart breaking. Sammy is dying and Cas has abandoned him.

Castiel can no longer stay away. He steels himself for what he must do.

"Well. It's about time. I've been screamin' myself hoarse out here for about 2 ½ hours now."

I know. God I know. "What do you want?"

"Well you can start with what the hell happened in Illinois?"

Everything. He starts walking toward Dean. A moth to a flame. "What do you mean?"

"Oh cut the crap! You were gonna tell me something."

Don't. Please. "Nothing of import."

"You got ass-reamed in Heaven but it was 'not of import'?!?"

"Dean…" Castiel's façade is cracking. "I can't. I'm sorry." He turns away. Walks a few steps to pull himself together. To prepare to lie to the one man in the world… "Get to the reason you really called me. It's about Sam right?"

"Can he do it? Kill Lilith? Stop the apocalypse?"

"Possibly, yes. But as you know, he'd have to take certain… steps."

"Crank up the hell-blood regiment."

"Consuming the amount of blood it would take to kill Lilith would change your brother forever. Most likely he would be become the next creature that you would feel compelled to kill." Castiel can hardly believe he got the words out.

"There is no reason that this would have to come to pass Dean." He moves in for the kill. Feeling sick. "We believe it's you Dean, not your brother. The only question for us whether you're willing to accept it."

Dean doubts. Not whether he will do it. Of course he will. He will do anything for Sam. What Dean doubts is whether he can do it. Whether he's strong enough. Whether he's special enough. He is. Castiel knows this with every fiber of his being. "Stand up and accept your role. You are the one who will stop it."

"If I do this, Sammy doesn't have to?"

Dean is going to sacrifice himself for his baby brother once more. And Castiel is the one asking him to fall on his sword. The pain rips through him. "If it gives you comfort to see it that way."

"God you're a dick these days." Castiel wishes he could explain. Wishes he even understood what was happening himself.

Dean walks away, not able to look at his betrayer. "Fine. I'm in."

Cas recites the pledge. "Do you give yourself over wholly to the service of God and his angels?"

Even with his back turned Castiel knows Dean is rolling his eyes. "Yeah, exactly."

"Say it." Dean turns and looks at Cas like he is a complete stranger. Cas wills him to see the pain in his eyes- to know that he is sorry for this. For everything.

Dean walks back to Cas slowly, eyes locked. Forcing Castiel to see the damage he is inflicting. "I give myself over wholly to serve God and you guys."

"Do you swear to follow his will and his word as swiftly and as obediently as you did your own father's?" Mentioning John is low blow. Cas is sure that's why Zachariah insisted on it.

"Yes, I swear." Castiel nods slightly. The deal is done. "Now what?"

"Now you wait. And we call on you when it's time." They stand there staring into each other's eyes. Both unwilling move. As angry as Dean is, as disappointed and hurt, there is still a tiny part of him that believes in Cas. That doesn't want him to disappear. Is comforted by his presence. Cas can feel it. He can feel everything.

Never in his existence has Castiel been so attuned to another being. He never imagined feeling anything, much less the torment of the sad beautiful soul before him. And he was about to make it worse. Dean would never forgive him for this. That last bit of hope and trust would die and Cas would be just one more person who lied to him. Let him down. Used him.

Cas fights the urge to reach out and touch him. To lay his hand over his mark on Dean's arm and grip him tightly. Or gently brush his soft cheek. Or to fall to his knees and beg his forgiveness.

Dean, on the other hand, is fighting the urge to punch him. To take out his frustration on the beautiful angel standing before him. To hit him again and again until he is spent and collapses in tears holding on to him for dear life.

But they both resist.