A/N: This is for Miyth, who wanted a Sam&Cas friendship story since Sam's attitude on the show lately has been abysmal. So here's me, not only providing those friendship feels, but also trying to fix Sam's behavior from the last episode.

Disclaimer: Don't own Supernatural. Spoilers for 11x18 "Hell's Angel." Thanks to 29Pieces for beta reading. ^_^

"Live and Let Die"
Part One

Sam stood in the doorway of his brother's room, gazing sadly at Dean passed out on the bed. An empty liquor bottle sat on the nightstand. It wasn't the first of tonight's binge, just the one to top it off. Sam knew Dean was at his wits' end. The reason being the comatose angel lying in the room across the hall.

Amara and Lucifer were gone. The Darkness had gotten cocky or whatever, and decided to eat Lucifer's grace. Sam would never forget the archangel's terrified face as Amara cupped his head and leaned in, mouth stretching wide. Lucifer had bucked and choked, but he was powerless against her. Sam had figured their time was up, too, but then Amara had doubled over, clutching her chest. The Darkness wasn't meant to consume so much light, especially that of the Morningstar. And she'd exploded.

That'd been two weeks ago, and there hadn't been any sign that she might have survived. Sam was still holding his breath, just in case, but it seemed the two most evil beings in the world had actually destroyed each other without much fuss.

Then there was Cas. They knew Amara hadn't devoured him along with Lucifer, because there was a split moment after she'd consumed the archangel where Cas was left gasping, eyes wide in shock, before he went into a seizure and collapsed. But despite surviving everything, the angel hadn't woken up since.

Sam cast one last worried look at his brother, and then turned toward Cas's room. He'd been waiting for Dean to drink himself into oblivion before trying this. It wasn't that he wanted to keep his plan a secret from Dean; he just didn't want to give him false hope, because there was a good chance it wouldn't even work. Also, it was kinda risky entering the mind of someone in a coma. Sam had found a spell to tweak the African dream root potion in order to make it doable, but it wasn't a tried and true method.

Still, Sam was willing to try anything other than watch his brother slowly fall apart.

He entered Cas's room and shut the door, then moved to sit in the chair next to the bed where Dean spent most of his time when awake. Cas was completely still, chest barely rising and falling with shallow breaths. His pallor was pale, save for the dark circles under his eyes. He looked as bad as when he'd been under Rowena's curse. Worse, actually, because if not for the slight breathing, Cas looked…dead.

Sam took a deep breath, and downed the potion. Then he leaned back in the chair and waited for it to take effect.

He had no idea what he would find inside Cas's head, but the bunker's kitchen was the last thing he expected. For a moment, Sam wondered if he'd done something wrong, if the potion hadn't worked and he'd gone to make a new batch…even though he didn't remember getting up and walking down the hall.

But faint noises came from behind him, and Sam turned away from the pantry to find Cas sitting at the kitchen island, watching TV. Sam blinked in bewilderment, glancing around again for any sign that this was in fact Cas's head, and not his own.

"Uh, Cas?"

Cas looked up briefly from the television. "Oh. Hello, Sam."

Sam's brows rose as Cas went back to watching TV. "Cas, are you okay?"

"Fine." The angel reached over to adjust the antenna.

Sam stared. This was not at all what he'd anticipated… "Okay, well, it's just that you've been in a coma for a couple of weeks, and Dean and I are worried. Why aren't you waking up?"

Cas glanced over again, quirking a brow. "Why would I wake up?"

Sam sputtered. "Because Amara and Lucifer are gone. We won, Cas. We—you—saved the world."

A small smile crept onto Cas's face. "That's good. I thought as much, when I felt Amara rip Lucifer out, but I wasn't sure. Thank you for telling me." His gaze returned to the television.

Sam gaped at him. What the hell? He stormed over and roughly took Cas by the shoulder. "Cas, what's wrong with you? What did Lucifer do?"

"Nothing. You don't need to worry, Sam. The Darkness and Lucifer have been defeated. Everything's fine."

"Everything is not fine, Cas. Your vessel—" Sam bit his tongue. Dean had been right; Cas's body wasn't a vessel anymore, it was him. Had been him for years, probably ever since Jimmy Novak's soul left. "You are losing weight. Your body's deteriorating like…like you're human."

That had been a fear, too, that maybe when Amara consumed Lucifer, she'd taken part of Cas's grace with the archangel's. They just had no way of knowing if Cas didn't wake up and tell them.

Cas canted his head thoughtfully. "Well, that's not surprising. I'm not fully human, but I'm not fully an angel anymore. That's how Lucifer was able to possess me to begin with."

Sam's stomach tightened. "Okay, so what can Dean and I do to help?"

Cas waved a hand dismissively, and reached to fiddle with the television set again. "You don't need to do anything." He paused, brow furrowing as he angled his head up at Sam. "This has been taxing for you and Dean, hasn't it? I'm sorry. Maybe I can speed up the process. I'm frankly surprised it's taken this long for the body to expire."

Sam's heart jolted with terror. "Cas, I didn't come here to ask you to die quicker! I came to find out how to help you wake up!"

"I don't need to wake up," Cas replied blithely.

Sam's pulse throbbed wildly in his throat. What the hell was going on? Had Lucifer brainwashed Cas? Sam of all people knew how well the Devil could play mind games, but this…this lackadaisical Cas was downright frightening.

"Cas," he pressed. "You accomplished what you set out to do—Amara was defeated, and Lucifer isn't a threat anymore."

Again, Cas gave a small smile. "And now I'm waiting for the last piece. I knew when I said yes to Lucifer it would likely end in my death."

"But you don't have to die!" Sam shook his head in mounting frustration. Something was definitely wrong with Cas, but Sam had no idea what. Or how to fix it. He didn't know whether to be glad he hadn't included Dean on this plan, because seeing Cas like this would probably devastate him, but at the same time, Sam wished his brother were here to get through to Cas.

Sam glanced around the kitchen again, grasping for anything to help him. "Why does your mind look like the bunker?" he asked.

"Hm?" Cas hummed distractedly, focused on the television. "It's peaceful here. A sanctuary, almost."

"But…why the kitchen? Why not the library, or even your room?"

Cas glanced up, forehead creased in confusion. "My room? Oh, the place you and Dean let me sleep when I was recovering. I didn't want to impose, even if all this is just in my head." He let out a small chuckle that sent chills down Sam's spine. "I can stay out of everyone's way in here," Cas continued. "Plus, it gets good reception."

Sam swallowed hard. What was he supposed to do? Just…leave? Go back and tell Dean that Cas didn't want to be saved—again? But…it was different this time. When Cas had chosen to say yes to Lucifer, even if it meant dying in the big battle, Sam had wanted to respect the angel's decision. He didn't want Cas's sacrifice to be meaningless by convincing him to eject Lucifer before the Darkness was defeated. Not like what Sam went through with the Trials. He'd been ready to die if it meant closing the gates of Hell. But then Dean had talked him out of it, and why had Sam listened? If he hadn't, if he'd just gone through with it…

Because Sam had almost died anyway. And he'd still been ready. But Dean couldn't accept that. And Sam swore he would never dishonor anyone by forcing life on them if they didn't want it, especially if the greater good was at stake.

But now that he was standing here in front of Cas, who was ready and willing to die…Sam found himself unable to just walk away and leave his friend here. And he was beginning to understand what his brother had been thinking and feeling when Dean had faced this with Sam. Cas didn't have to die. The greater good had been accomplished, and Cas could live. So, didn't that make turning down life the true act of dishonor here?

Sam's throat constricted. "What about me and Dean? If you die like this, it's gonna tear us apart."

"You'll get over it," Cas replied nonchalantly. "It's not like I haven't died before." He let out a heavy sigh. "I just hope this one sticks."

Sam felt as though he was gonna be sick. Was this what Dean felt when Sam said to let him go? This clawing fear and horror at watching someone he cared about just give up? Without regard for those left behind? Sam knew Dean would be devastated if he died, that it'd be hard for his brother to adjust. But Dean had done it before, after Sam had jumped into the Pit. And…Sam had started building a life with Amelia after he thought Dean had died.

If he was honest with himself, though, there had been nothing easy about it. He'd woken every morning feeling as though part of his soul had been gouged out. And time didn't make the pain and grief go away. Sam could bury it behind a 'normal' job, behind a relationship with Amelia, even pretend to grieve properly when she talked about her deceased husband and he talked about his deceased brother. But in that year, had Sam 'gotten over' Dean's death?

No. And finding out Dean was alive had been a resurrection for him, too. Then when Metatron had killed Dean, Sam had been determined to bring him back. Dean had sacrificed himself by taking on the Mark, and told Sam to let him go. Their roles had been reversed, and Sam hadn't respected his brother's wishes. He'd justified it because Dean was a demon and obviously wasn't thinking straight. It was a completely different situation.

Sam glanced at Cas, who was fixated on the TV with unnatural intensity, flickering light from the screen reflecting in glazed over eyes. Sam had seen him like this before, after Rowena's spell…

"Cas?" He cleared his throat. "Why did you say yes to Lucifer?"

Cas didn't even look away from the monitor. "We needed him to defeat the Darkness."

"Yeah, but why you? We could have let him out of the Cage another way."

"I was the best option," Cas replied, and held up a hand to tick off the reasons. "I wanted to be of service, and had nothing left to offer anyway. I'm expendable. And that way Lucifer wouldn't be after you as a vessel; you'd be safe and Dean wouldn't be worried."

A spiky lump settled in Sam's throat. Oh, he'd been such an idiot. Cas hadn't said yes out of some misguided, noble effort. He hadn't weighed the value of the world and decided it was worth it to make the sacrifice. No, he'd thrown himself at the first grenade he found out of desperation and feelings of worthlessness.

Sam had been right; Cas didn't want to be saved. But for very different reasons. And Sam realized he couldn't sit back and watch this happen.

But how was he gonna convince Cas to change his mind? Plus, something else was going on here. Cas wasn't acting like himself, and Sam needed to figure out why.

"Um, mind if I sit and watch with you a bit?" he asked, feeling awkward just standing in the kitchen.

"Sure," Cas replied. "But you shouldn't stay too long. I'm not sure what will happen if you're here when I start to go. And I hear the final decline can happen quickly."

Sam's stomach churned, and he gritted his teeth against a surge of bile. Instead of responding, he dragged a stool over and sat down next to Cas. Sam didn't pay attention to the television program, however; instead, he was trying to wrack his brain for a solution to this problem.

He found his gaze roving around Cas's mental construct of the bunker's kitchen. A shadow fluttered in the corner, and Sam instinctively tensed. But as he squinted at the counter, he noticed the shadows were small, almost like oval wisps of smoke.

He sucked in a sharp gasp. No, they were feathers. The harder he stared, the more the air wobbled as though a mirage was fading, and Sam started noticing piles of feathers strewn around the kitchen. Not only that, but there were cracks in the walls. Small ones, and Sam wouldn't have been able to tell if they were authentic from the actual bunker if it weren't for the fact that they ran in congruent lines down the counters and across the floor. This mental construct in Cas's mind had hundreds of micro fractures running through it.

"Hey, Cas," he said, swallowing around a dry mouth. The angel didn't even look away from his program. Sam fought to keep his voice steady. "What was it like, when Lucifer was possessing you?"

"Why do you ask?" Cas replied, eyes trained on the screen.

"Because I've been there, remember? It…can be intense."

Cas hummed in apparent agreement. "It was uncomfortable at first. An archangel's power is tremendous. I remember being shoved down into a deep, dark recess, unable to see or hear what was happening." Cas cocked his head. "Until I felt your pain when Lucifer attacked you. I managed to fight my way up to regain some control then."

Sam unconsciously lifted a hand to his chest, almost feeling the phantom pain of having a fist shoved into his soul. He remembered the disbelief—and sense of betrayal—when he'd found out Cas had willingly released Lucifer. Was Sam's insistence that Cas ride it out some kind of passive punishment in return for letting the Devil loose on the world, after Sam had fought so hard to keep Lucifer in his Cage?

He didn't want that to be true, but there was an ugly twisting in his gut that whispered maybe a small part of him had thought, 'Screw you, Cas. You made your bed and now you have to lie in it.' The idea made Sam sick.

"Thank you for that," he said in a low voice, hoping his shame didn't bleed through.

Cas seemed oblivious to Sam's emotions and gratitude as he simply continued, "I thought Lucifer would punish me after that." Cas shook his head with a small smile. "But instead of causing pain, he took it all away."

Sam straightened. "What do you mean he took it all away?" Was this when the brainwashing happened? Some kind of Stockholm Syndrome because Lucifer needed to ensure Cas wouldn't pull another coup on him?

"Lucifer took all the things that made me weak, that made me more human than angel," Cas explained. "Messy emotions, you know. He locked them up somewhere so they couldn't hurt me anymore, which meant I was stronger to help Lucifer in the fight."

Sam's jaw tightened. That definitely sounded like some kind of brainwashing, and must be the reason Cas was behaving like this blasé, stoned out persona. Lucifer had locked up the angel's emotions—but what did that mean, and how did Sam reverse it? Because he'd never be able to convince Cas to fight to live if he couldn't get his friend thinking straight again.

So how would it work? Sam gazed around the kitchen. If Cas's mind found refuge in the bunker, then there must be more to the construct than just this one room. Sam stood in a rush.

"Cas, how about we go for a walk?"

"No thanks."

Sam clenched his fists, fighting the urge to throw the stupid TV against the wall. But he wasn't sure if that would shatter the growing chinks branching out like crackled glass across Cas's mind.

"Cas—" Sam forced down an exasperated tone. "I'm not gonna be able to stay much longer. Please? I'd rather…rather spend the time with you, not the TV."

Cas glanced up, brow creased in thought. His shoulders finally sagged. "Alright, I guess a short one would be fine."

Sam watched as Cas reluctantly pried himself away from the television monitor and started shuffling toward the hallway. The air bent in Castiel's wake, shedding another feather to land on the floor and crumble into ash.

Sam's pulse ratcheted up, and he hurried to get away from the kitchen. He followed Cas into the library, and watched the angel's gaze drift fondly over the bookshelves and study tables.

Sam didn't know what to make of the fact that Cas felt at home in the bunker, and yet didn't actually consider it his home. Cas had said he thought he was imposing? That his room was just where Sam and Dean 'let him sleep'? Guess that went with not thinking the Winchesters would care if he died, or thinking he was 'expendable' in the first place, and what the hell was up with that? Was that also some twisted lie Lucifer had brainwashed him with? But, if Cas believed that before he'd said yes, then it couldn't have come from Lucifer. So where had it come from?

Cas had said the emotions Lucifer took from him had been painful. What had Cas been going through that Sam and Dean hadn't noticed? Hadn't bothered to notice.

"Cas," Sam started. "When did you start thinking you were expendable?"

Cas lifted a hand to run his finger along the spines of some ancient tomes. "I only recently figured it out, just before Lucifer. But I was broken—used up—long before that."

Sam's heart twisted at the casual way Cas said it, like there was nothing wrong with thinking of himself as worthless and expendable. "Rowena's spell?" Sam hazarded.

"That certainly made things worse," Cas admitted. "But even before that." He turned to give Sam a contemplative look. "You know, I was never made right. I was a terrible angel, and screwed up everything, no matter my good intentions. Actually, when you think about it, it's a miracle my role with Lucifer didn't jinx the whole thing."

Cas shrugged then. "You and Dean are better off without me."

Sam surged forward. "Cas, that is not true. You're family!"

Cas smiled, and patted him on the shoulder. "That's nice of you to say, Sam."

Sam could only stand there, fumbling for words as Cas went back to perusing the bookshelves. Was all this really how Cas felt? Was it the reason he'd said yes to Lucifer? To get away from…all of it?

And Sam had blindly said, 'Cas chose this. Let's respect his wishes.' Cas hadn't chosen it, not really. He'd been drowning right in front of them, and the Winchesters hadn't realized it. Hadn't done anything to help him. Sam couldn't let him go, not like this.

He whirled and started frantically scanning the room in search of a clue, anything to suggest how Lucifer might have locked away Cas's emotions. The Devil liked games, even poetic imagery, so Sam just had to think like Lucifer. Which, given that Sam had also been in the archangel's head at one time, shouldn't be impossible.

"Oops," Cas said, drawing Sam's attention just as a book disintegrated in the angel's hands and rained dust down at his feet. Cas pursed his mouth. "Hm, you should probably go now, Sam."

No, he needed more time! They were in Cas's head, which meant there had to be a way to access everything Lucifer had disconnected and locked away. So where would Lucifer put it, knowing Cas would never go?

Sam considered the dormitory wing, but no, Cas had spent a lot of time watching Netflix in there back in the real world; it was just as good as the kitchen, even if he was trying to 'stay out of the way'. The dungeon? Cas had no reason not to wander in there, though.

Come on, think. Was there any place in the bunker Cas would never go? Sam couldn't think of any… Wait, maybe that was it. He spun sharply and sprinted out through the war room and up the stairs toward the front door.

"Sam, where are you going?" Cas's voice called out behind him. "That's not the way out for you."

Sam came to a stop in front of the heavy iron slab, which was barred with several chains and Enochian scratches in the metal. Of course. Cas was waiting in his sanctuary to die; he'd never leave the comforting safety of the bunker.

Sam tugged at one of the chains. There was no lock that he could see, not that he had a key for it anyway. He moved down the catwalk to get the axe from next to the fire extinguisher.

"Sam, you shouldn't do that."

Sam ignored Cas, and swung with all his might at the chains. Sparks flew as metal clashed. He attacked both the chain links and the door itself, gouging through the sigils carved into the seal.

"Sam!" Cas shouted from the bottom of the stairs.

He paused long enough to glance over his shoulder at the angel, who seemed too nervous to climb the steps himself.

"Please don't," Cas said.

"Cas, you have to face these things; you have to be whole again. Don't you get that you're dying?"

Cas just gave him a resigned look. "That was always the most likely possibility."

"But it doesn't have to be that way!" Sam nearly yelled. "Dammit, Cas, you can come back from this!"

"I don't want to."

Sam recoiled as though the words had been a physical blow. He'd said the same thing to Dean once. And his brother had ignored him, tricked him into becoming an angel condom.

But for all of Sam's talk about letting Cas go, of respecting the angel's wishes the way Dean never did…it was a whole other matter to stand in front of his friend and hear it to his face.

Sam turned back toward the locked door and swung the axe again. Metal collided with a resounding clang. "I'm sorry, Cas, but I can't let you die." He hacked at the door, finally breaking one of the chains.

"Why are you doing this?" Cas asked, a hint of strained emotion finally leaking into his voice.

Sam's heart clenched, and he let the axe thud on the floor as he looked back to meet Cas's gaze. "Because you deserve to be saved. Because Dean and I care enough about you to dive into this black hole and bring you back."

Sam smiled sadly. He'd been so angry with Dean for doing that to him, but he now realized he was also grateful to have a brother willing to go to the ends of the earth for him, to defy death for him. Cas thought the Winchesters would just 'get over' him dying; he didn't believe Sam and Dean would fight tooth and nail for him.

It'd been true, too, to Sam's utter shame. He hadn't fought for Cas like Dean had. In fact, if Dean had been the one to say yes, Sam would've stopped at nothing to get him back. How could he not have done the same for Cas? How could he have let it get this far? He called Cas family, but didn't treat him that way. And it was something Sam needed to rectify.

So he turned his back on Cas's pleading expression, and heaved the axe up in one mighty swing. Steel cracked, and the chains broke apart. The sigils glowed red before fizzling out. Taking a deep breath, Sam gripped the door handle and wrenched it open.

A/N: Stay tuned for Part Two on Friday. :)