AN ~ because Stairway to Heaven was FREAKING AMAZING. So much got brought up that I thought would be left to the meta analysts and authors like me. Loved it loved it loved it. I literally threw my computer about a metre and my hands were shaking for ages afterwards! Thus, I have lots of feels to write with. This follows straight on from the last scene of 9x22. MAJOR SPOILERS.

Now I Lay Me Down to Sleep

When Dean calms down enough for it to be safe, Sam wrenches the blade from his brother's hand and throws it across the room.

"What the Hell Dean?!" he shouts, pacing a few steps away, arms wide, demanding an answer, even though there's nothing that Dean can say at this point that he would believe. Thoughts fly violently around his mind like so many distressed pigeons. His limbs are useless. He doesn't think he's ever been so angry with his brother in his life.

Dean stalks a few steps forward from Cas, shoulders still braced but crisis moment over. He eyes his flaring brother but doesn't try to answer the question. He knows he can't say anything Sam will hear. Instead, he looks back to Cas, who still has not moved.

The Angel's eyes are focused straight ahead. Dean follows his gaze to Gadreel, who is slumped in the middle of the floor. The white-silver light is gone now, leaving behind only dark, shimmering blood – and of course, the shadow imprints of wings reaching out to either side.

"I'm sorry, Cas," Dean says, and the words feel like a lie. He wants to be sorry, he does. But he is not.

Castiel's lips move, as if trying to form a word. Dean, probably. But no sound will pass his throat, so Cas gives up. He moves slowly past the human for whom he has lost everything, and kneels beside Gadreel. For several seconds, he stares softly at the other Angel's face.

Dean grits his teeth and walks away, to his room, slamming the door behind him.

Sam lets the adrenaline, the shock and the rage wash through him until his shoulders loosen up and his breathing quiets. Eventually, he leaves the Angels too. When he gets to his room, he closes the door with a sigh and leans back against it, letting his head fall back. As he stares up at the roof, it feels like staring up at the whole world, hanging on a string above him, and somebody he doesn't know is holding the scissors. Everything is falling apart. It has been for a while now, of course, but now it is accelerating. Vaguely, he feels a craving for the sense of control that demon blood had once given him. He presses his palm and grits his teeth against the phantom pains that shoots up his arm. Magic this strong comes at a price.

"Why won't Dean take me seriously?" he whispers to the roof, the world, and the sky. "Why does he have to treat me like a kid?"

He closes his eyes. He knows the answer, and it's no better than not knowing. The fact that Dean's trying to be helpful and protective doesn't make it any more of a right decision, and it doesn't help Sam make his brother see what is going wrong.

God. Please help me.

He used to pray every night. He's let the habit drop off recently, and knowing that Metatron is God, or is at least filling in while the real God is off…well, God knows where…It makes the words hollow. Sam stops praying. He sighs. He stands, and drags himself over to his bed, and lies on his back on top of the covers.

Hours pass. He might have fallen asleep a few times, he's not sure, but at least his mind has cleared by the time he hears a knock at his door.

"Nyeah," he groans, slipping one hand under his pillow, just in case. He lets his fingers retreat from the pistol when he sees who it is.

"Can I join you?" Cas asks quietly.

"Sure, sure." Sam beckons him in, hauling himself into a sitting position as he takes in how insecure the Angel looks. His shoulders are hunched slightly, his head lowered, eyes scanning the ground aimlessly as his hands hover between clenched and unclenched. He paces the room a few times before he speaks.

"Sam," Cas says. His voice is quiet, but Sam is not sure if that's to prevent being overheard, or because he can't speak any louder without the shaking, the distress, the doubt being more obvious than it already is. Sam just nods, and waits for Cas to find his own words to continue.

"Sam, I'm scared."

Sam swings his legs around, so that they hang off the side of the bed, and listens.

"I'm scared we're going to screw up. I'm going to screw up." Cas paces faster, like a caged animal. "This grace inside me, it's killing me. I could cut it out, maybe, I mean I don't know what would happen. I don't know if my own grace is destroyed or not. I don't know whether or not Metatron was being honest when he offered my followers amnesty. What if they're dead, Sam? What if they're dead because they couldn't trust me?"

"Okay, slow down." Sam holds up his hands. The Angel obeys, his desperate eyes seeking out Sam as he settles in one place.

"I don't know about your grace either," Sam begins. Lying is what got them into this mess, after all. "I don't know what Metatron might do to your followers. But remember, they are the ones who chose not to trust you. You never ordered those hits. You haven't done anything wrong."

"But I have," Cas protests. He starts to pace again, and Sam grinds his teeth together. The caged-animal vibe is putting him on edge. But Cas is his friend, and needs help, so he will listen even if it drives him mad.

"I've killed Angels before," Cas confesses. It's not a revelation but it starts the words flowing. "Not just Michael. Not just the insane massacre in Heaven. I've stabbed and slashed my way here. I betrayed Anna. I betrayed you and Dean. I killed Raphael and several of his followers before the power of those souls even really started going to my head. I shoved a bullet into someone's eye. An Angel's eye. My brother. We went through training together, thousands of years ago, and I killed him. I killed Samandriel, too. He was good. I killed Balthazar. My friend. The only one who was willing to stand by me even when I was completely insane. Of course, I later found out he was intending to betray me for my own good, but…"

He shakes his head and turns to face Sam. There is a darkness in his eyes that the younger Winchester recognises well.

"Do you know what I did to get this grace?" Creeping closer and closer to Sam, Cas explains. "I slit another Angel's throat. An Angel that was willing to help me. I consumed his grace and I left him to die. Not even Metatron did that to me, Sam."

The Angel's nose is inches away from Sam's. They stare at each other for a moment, and Cas swings away, sitting on the bed next to Sam and looking listlessly at the two hands folded in his lap.

"Jesiah was right, I think," Cas continues, softly. "I'm not an Angel. I don't deserve to be one, at least. I'm not a leader. People cannot have faith in me."

Sam tosses up his next words for a moment before he decides to lay them out.

"I think Dean can."

Castiel laughs briefly. "The blind leading the blind."

"In all honesty? Maybe. But you know what? Dean never used to pray. Well. I mean, I think he did once, a long time ago, but then when Mum died, and Dad died, and Jess died – and Hell, I died…I think it just sucked whatever faith he had, right out of him. When you finally showed up he was adamant you weren't a real Angel. But you know what? He prays now. When I was sick after the trials he prayed like Hell. He prayed to you.

And as for what happened today? Dude, you gave up an army for one man. You stood by your principles even when it cost you big. You've learnt from your mistakes and you stick by your decisions. That sounds like a leader I want to follow."

"But what about Dean?" Cas presses. "The Mark…it's doing more than you know, Sam."

"What, Dean's gonna try and kill me? I've thought of that, Cas. I did read the Bible. I've got a pistol filled with angel blade bullets under my pillow and everything, don't you worry about me."

Cas looks up at Sam, frowning.

"You would…kill…Dean?"

Sam sighs and looks forward.

"I don't want to," he clarifies, "and look, I'm not going to do something unless absolutely necessary. Of course I'm not. But Dean never would have wanted to become this. You shoulda seen him talking about Hell, Cas. How ashamed he was. How scared of himself. He actually cried. Tears. I have never seen him do that before or since. And it scared the shit outta me. And I won't let him kill me, or you, or anybody else who doesn't deserve it. Gadreel didn't. I'm sorry."

Cas nods, contemplating what Sam has said. He's in no state to criticise Sam's plan, or lack thereof, at present, but the younger Winchester's last words draw him out of his anger and fear, and back to his grief.

"He was trying to redeem himself," Cas murmurs. "I thought I'd gotten through to him. I held out hope he'd change his mind. When he finally did I thought 'this is it, this is what I can do'. If I could successfully stop him making the same mistakes I did, I thought maybe…"

"I know."

"Another Angel I couldn't get back home."

"I know."

Silence. Sam looks at Cas and forward again. Cas looks at Sam and down again. Their uneven breathing is the only sound until Cas sighs, and it seems as loud as shattering glass.

"I'm sorry for waking you," he says, standing up. The frown remains fixed on his brow as he moves towards the doorway. "Thanks for listening."

As Cas pulls the door open, Sam calls out to stop him.

"You saved my brother, Cas."

Still holding the door open, Cas looks back at him. He locks his eyes on the Angel's and embraces the last moments of this honesty.

"You saved him. I'm not just talking about today. Back with Michael too. You could have let him walk into that, and you didn't. And more times since then, I'm sure. But look, my point is: he's screwed up, and I've screwed up, and you've screwed up, and here we all are. We might be all we have left, but you know what? We stopped the Apocalypse. We can figure this out."

Cas nods. He doesn't look convinced, but it's a start. He lets the door close itself behind him, and Sam sighs as he lies down again, and closes his eyes. It's gotten colder. He rolls onto his side and curls up. His fingers brush the metal of the pistol under his pillow again.

Come on, Dean, he pleads. We can figure this out.