Sam was missing.

It was an obvious fact, emphasized by the disarrayed motel room that Dean came back to at three in the morning after a drunkenly (and probably sexually-involved) social gathering. Book and papers were strewn all over, the one window was shattered, and there were dark, ominous-looking splotches of blood on the floor. Seeing the room, as well as calling all of Sam's numbers at least twenty times before finally calling Castiel, sobered him up to an impossible degree.

And Castiel could understand why. Because whatever was running through his vessel's veins right now, keeping the angel more on-edge than any other substance in existence, was also what he could see clearly on Dean's face, in every tensed muscle, in the way his hands clenched and unclenched and shook: panic.

After Dean told him what happened, Castiel took off right away. His heart was beating at an unnatural rate as he searched every corner of the sprawling New England town with a sense of urgency and vigor he hadn't felt since the final seal was about to be broken. Except this time, everything driving him was purely emotional. Every bit of his grace that seeped through his skin cried out one thing: Find Sam.

Neither Dean nor Bobby could do more than try to scope out for the human themselves, since getting other hunters involved proved to be unwise last time, according to Bobby (and Dean said he was going to hear that story as soon as Sam was safe and sound). Castiel could travel faster with his ability to fly, but the sigils that he had carved onto Sam's ribs were preventing him from honing him down. He had to search in an infuriatingly human-like manor, checking every corner with his own eyes, his grace proving useless. Much of Castiel was proving useless nowadays, with his grace dwindling at the rate a plant wilts in a drought. It was a new feeling for him, one that ate away like something poisonous at the roots of his soul. The angel almost longed for the days where he was constantly affirmed that he was doing right by the will of God, that he was making a difference. Nowadays, he was stumbling, unsure. And for the first time in his life – desperate.

Perhaps that's why Castiel had been starting to take something close to a liking to Sam. Although it would've been easier to simply keep seeing him as "The Boy with the Demon Blood", once Castiel fell, the angel could no longer judge him at the lofty height he used to. Since he was no longer being bombarded with orders from his older kin or giving orders to his younger siblings, Castiel found himself overwhelmed by the silence in his mind that used to be a filled with a constant rattle of voices. When he wasn't searching for ways to stop the Apocalypse, the angel, for the first time in his existence, had time to truly think. So he pondered on those he fell for. On Dean, Bobby, and most frequently, Sam.

His anger towards his brothers and towards his human friends after Lucifer was released caused him to lash out at Sam once for being unable to make the right decision. But that anger had simmered down to a low boil, and after stepping back, Castiel couldn't deny that Sam truly did what he thought was right at the time. And honestly, with his fallen status, could Castiel call himself any better? He had lied to Dean, manipulated Sam, all because he never bothered to question what he thought must be right after two millennia of service. It was hard for him to admit the sin to himself, and both strange and uncomfortable to draw the comparison between him and the demon blood-tainted human. At least at first.

The longer that he spent with Sam, though, the more Castiel could see the easy-going, kind-hearted man that Dean once knew and still tried so hard to see, even after everything fell apart around and between them. After many conversations and meetings, Sam transformed from someone – or rather something – that could be seen as 'not a threat' on the best of day, into someone whom Castiel actually enjoyed spending time with on occasion. He was smart, had a surprisingly easy temper when his system wasn't infected with demon blood, and quite obviously cared very deeply not just for his family, but for humanity as a whole. Sam was fighting with everything he had to save the world he accidentally destroyed in order to save the unknowing people within it. And, when Castiel thought about it, what could truly be deemed evil about that?

It wasn't until Sam fell under threat, however, that Castiel realized how much the human had come to mean to him. When Anna told him that Sam had to be killed, his logical and collected mind that usually dominated his decisions told him that Anna's plan was actually a sound one. But something deep inside of the angel screamed in protest. The angel, still unused to the tidal waves of human emotions, was taken aback by the complete and utter revulsion he was hit with at the concept of Sam dying. If that part of him had never existed, he still would have protested for Dean's sake, true - but this was a selfish need, one that was only connected to Sam and his well-being. Because Sam was his – friend. He hadn't realized it until that moment when the word rattled then flattened out resolutely in his mind. And as he straightened his back and set his face into an expression of cold determination, it was made clear that the angel would be willing to kill anyone who wished to cause Sam harm, even a fellow sister. Because now, after Castiel's entire world had been turned upside down, there were few things the angel could imagine worse than his friend being killed and being unable to be brought back.

So when Sam disappeared, the angel had no qualms stopping the search for his father and looking for Sam instead. Both Heaven and Hell had it out for him, and a good number of those in-between did as well. The list of who may have taken Sam was far too long, and 13 hours had already passed since he was taken. That horrible and still too foreign feeling of panic was rising like a tide in his chest, knowing that Sam would probably be dead if a human or monster took him, and even worse off if a demon or angel found him. Neither Heaven nor Hell could kill him – or keep him dead – but Castiel knew all too well that both sides were precise masters at torture. He swallowed at the thought, and started to search faster.

He was running down a busy road when he finally heard it – the laugher. It was deep, rich; a perverted chorus. Something that was smothered, but recognizable by those who knew how to listen. Angels could communicate and filter in one another, but Castiel had been very severely cut off from Heaven. He shouldn't have been able to hear any of his kin.

Unless they were rebels. Not cut off from Heaven, but hiding from it. Castiel hadn't run into many of them before, but he had heard of their kind before he fell. He wondered why he could hear their graces as opposed to the rest of Heaven.

And then, he heard the scream.

He immediately recognized the owner, though he'd never heard him scream before. It made his guts convulse at what could have made that usually deep but soft voice cry out so fiercely and painfully. That thing inside of Castiel, that freshly-born creature that was so irrational, so breakable and so desperate, bat against his chest and screamed all over again: 'Save Sam. Protect Sam.'

Castiel flew himself over in a matter of milliseconds, tracking down the angels remarkably easy once he had traced the connection between them. He found himself in a secluded and dark alley, with dirty, abandoned apartment buildings on either side of him. He set his gaze towards the group. There were about ten of them, standing in a circle, in vessels of all shapes in sizes but wearing regular street clothes rather than the suits most of the angels were assigned to wear. Castiel could feel the reckless pulse of their graces, jubilant and completely ignorant as he walked towards them with his shoulders set back, expressing all the vicious fortitude of a lion preparing to kill its prey.

He was right in his assumption: they were rebel angels. Of the younger generation, too cowardly to actually fall, but not always obedient to their father's decrees. They were tricky, smothering their grace so that the elders couldn't track them down. They were unlikable and dishonorable, and Castiel was honestly ashamed to call them his kin, even before he fell.

But his feelings about them then were nothing compared to the fury he felt towards them now. As he approached, the laughter and the taunts began to slowly die away, realizing they had company. There was no doubt that they had heard of Castiel; his act of turning on his brothers were well known in all of Heaven if Anna's reports were to be believed. Most of his brothers hated him for it, but being different reaps its own legacy in the eyes of some, and the way these angels parted for him showed that odd sort of reverence, or at the very least, fear. Castiel was older, and his fame of escaping from a ring of Holy Fire while he was cut off from Heaven probably helped instill the angels with a healthy sense of cautiousness.

When the last angel parted, Castiel finally saw him. He was on the ground, his hands tied behind his back by an Enochian binding that only angels could destroy. Blood coated his lips, red and blue bruises and cuts covered his usually soft-edged face, and his chest was a massive array of welts. The fire in Castiel's belly burned at the sight of them – they were produced by an angel-made whip, the kind made specifically to tear and traumatize the flesh with its spikes, but also keep the victim from dying by bleeding out.

Sam was shaking on the hard ground, trying to bend his knees and fold into himself, into a safe and fetal position, but Castiel could tell by the way his right leg dragged that it was probably broken. His eyes were closed, his brows burrowed together. It was the most vulnerable, most utterly broken, he had ever seen the man. It made him wish that he could both heal those wounds and utterly smite those who created them in the first place.

"Hello, brother." One of the rebel angels, Zachiel, wearing a tall, blonde man as a vessel, had the audacity to approach as Castiel took a worried step towards Sam. He was even grinning, an expression that was eerily similar to the dark and ominous smile Lucifer had given him while he was trying to convince Castiel to join his side. In his hand, he held a long, black whip that Castiel knew too well from when the angel had disobeyed in the past. "I've taken it you've decided to join us?"

"Join you?" Castiel's voice was deep but clear, sounding just as offended, if not more disgusted, as when Lucifer asked him the same question. "Have you forgotten what our father decreed before man was even created? That we are not to lay a single hand on him unless He decrees it?"

His voice mounted and grew more and more deadly, and a few of the angels shifted uncomfortably, whispering between themselves. Zachiel, however, just laughed. "I'm sorry, but it's just strikes me as funny – the angel who turned against Heaven, lecturing us about what we should do in our spare time?"

"What I did -" Castiel started, taking a step forward and curling his lips, before a weak and choked word cut him off.

"Cas?" Sam's eyes were open now, just barely, shining with mostly pain, but also something akin to hope. Castiel's chest clenched at the sight, and he instantly reached for the beaten man.

But before he could touch him, Zachiel pulled Sam to his knees by his arms, clenching them tight enough to rub the bones together, causing Sam to cry out. At a proximity that made Castiel want to rip the angel in half for even daring to get that close to Sam, Zachiel hissed into his ear, "What gives you the right to speak to him, you filthy demon-blooded spawn? Given what you are, you should remain on your knees and not speak at all."

"Zachiel, stop." Castiel's voice, a voice with a power that he hadn't used since the time of Abraham and Isaac, got Zachiel to relax his grip on Sam's arms before they snapped. He pushed Sam to the ground before Castiel could catch him, falling flat on his abused chest and face.

"Yes, Father spoke of not harming the humans, but can you honestly count this one amongst his supposed kind?" Zachiel showed no signs of slowing down his monologue, stepping in from of Sam's bruised and beaten body, coiling the whip in his hand. "Even fallen, you know this creature is no man, and that he is not worthy of your attention. For eons you've known this." He got behind Sam again and, as Castiel practically snarled, dragged him upwards by his hair. He bent back his neck, leaving Sam open and ready to be ripped apart like a sacrificial lamb.

"So do what you know is right, brother," Zachiel said, and he put the whip into Castiel's hand.

Castiel just stared. He had never been assigned to disciplining those angels that went out of line, never had such a cruel weapon in his hands before. He never sought out such a position – even as a warrior, it wasn't in his nature to be ruthless. The whip, engraved with Enochian sigils speaking of grace and righteousness on the handle, felt like a poisonous serpent in his hands, slithering and unwanted, as he looked down at the kneeling form before him.

Sam's eyes were less hopeful than they were before, glazed with turmoil, but still lucid. They flickered to the whip that was laced with blood – Sam's blood, Castiel realized with a horrific jolt – and then back up to Castiel. The angel didn't think there could be anything worse than seeing the horror and pain on Sam's face that was there before. He was wrong.

His eyes weren't hopeful that his friend might be able to save him. They were accepting. Like a man before stepping onto the execution block, Sam swallowed, and closed his eyes. Not peacefully, but like someone who was preparing for the final blow.

Sam expected Castiel to hurt him.

And it made the angel, for the first time since he was created, want to die.

"Let. Go." Castiel wasn't sure if he was speaking through his vessel's mouth anymore, the power that rumbled through and around him surely too much for Jimmy's body to contain. Zachiel's haughty expression only slid about an inch, but he did what he was told. Castiel caught Sam this time, tossing the vile whip to the side before gently but firmly wrapping his hands around Sam's shoulders. Castiel whispered Sam's name, and Sam managed to open his eyes again. His expression was now confused, but still withdrawn, still expecting the worst.

Slowly, Castiel reached one of his hands to Sam's face, wanting to inspect the damage, wanting to offer some semblance of comfort to this cursed child who had been through far more than any human should –and Sam flinched away.

And something inside of Castiel snapped.

Like a violent storm, a fury equivalent to God's own washed over him. He reached back and burned off the bonds around Sam's wrists, and despite his overwhelming need to smite these sons of bitches into oblivious, he gathered Sam up in his arms as gently as he could, not even struggling as he used his grace and superhuman strength to lift him up.

Castiel wrapped one arm under Sam's legs, and the other around his back, careful not to aggravate the wounds on his chest. Sam slumped against Castiel, his body starting to go limp. Not with loss of life, but with weariness, and what the angel hoped, but didn't expect, was trust. "I am giving you once last chance," Castiel said, blue eyes piercing and still looking plenty intimidating as he held a giant of a man in his arms. "Heal him. Or you will reap the consequences."

"I would like to see you try," was Zachiel's immediate response. The angels beside him, who were obviously smarter than he, started to shuffle anxiously. As well they should.

Castiel couldn't kill them, that was true. But he could send out a beacon to Heaven to let them know of these rebels' whereabouts, as well as their transgressions. And Heaven was just as ruthless as Hell when it came to its servants disobeying orders. He should've felt guilty for the torment that awaited his brothers when Heaven found them. At that moment, though, Castiel couldn't find it in him to care.

"So be it."

Castiel's grace started to burn brightly, and finally, that smirk was wiped right off of Zachiel's face. A loud, humming sound started all around, and they all knew that Heaven had marked those still bound to them - which Castiel was not. Even if the angels managed to escape, Heaven would find them in a matter of seconds.

As terror started to bleed through the pitiful cluster, Castiel just held Sam closer to his chest, Sam's head tucked into the nick of Castiel's arm, before flying away. By the same the garrison arrived a few seconds later, they were already too late to capture the Fallen Angel and Lucifer's Vessel.

Several hours later, Castiel stood guard outside a hospital door.

As soon as he had gotten them away from the angels, he flew Sam to a hospital a state or so away, not willing to risk getting caught by Heaven with Sam already in such a weakened state, Castiel completely unable to heal Sam on his own. If he thought he felt useless before, it didn't compare to seeing Sam stretched out on a gurney, whimpering in pain, and being able to do absolutely nothing. Sam looked at him laid out, his expression crying out 'stay with me' in volumes undefinable to man,before they wheeled him into surgery and took him away. As soon as he was behind those ER doors and Castiel could do no more for him, he traveled to a random state and completely shattered a row of street windows.

He called both Dean and Bobby, and after a nice long yelling-session from Dean about why Cas didn't pick him up as soon as he knew something (Castiel knew by now that this was Dean's way of expressing his overwhelming fear for those he loved), Castiel transported them both to the hospital. All three of them proceeded to worry in their own ways, constantly asking if Sam was okay, was he out of surgery, could they see him yet? Threats were made, from both sides, until Dean finally relented, his need to see Sam stronger than his urge to punch out his frustrations on strangers in the face.

After what felt like an even longer day than the one previous, Sam was finally out of surgery. He had three broken ribs, a broken cheekbone, and his right leg was broken in two sections. They were lucky, the doctors told him – if they had come any later, Sam probably would've never been able to walk again. The damage to his chest was increased by the whip marks, which they also found on his arms and legs. The healing period would be long, but over time, Sam would recuperate and have all the functions he had previously.

What made Castiel sick to his stomach was that he knew things could have turned out so much worse.

Sam was awake now, talking, from what Castiel could tell. He could see him through the window of the tiny hospital room. All three agreed that it was probably best that someone stand guard until they could get Sam to the relative safely of Bobby's sigil-adorned home. The angel had taken the first shift, though inwardly he was still very impatient to check on Sam himself.

Dean sat next to him, worry palpable through his mask of a weak, cheeky grin. Sam muttered something, his face turning irritated as Dean punched him in the arm, though not even hard enough to bruise, before they both shared small, but meaningful, smiles with one another. Castiel smiled to himself a tad at the sight. Dean was tired – Castiel could see that plainly in every sagging muscle in his body, in every line in his face – but he was still trying, for Sam's sake more than anyone's. Though his brother betrayed him once, there was never any doubt to Castiel – and probably to Dean himself – that he'd never stop being Sam's big brother, his ever-present guardian. If Dean had been with Castiel at the time, he probably would've fired at least a round of bullets into each angel's head on the sole principle that they had dared lay a hand of his brother, all concentrated rage that Castiel never saw aimed towards Sam, but was always in the forefront of his behavior when Sam was threatened in any way.

The only one who doubted that Sam deserved that sort of fierce devotion was Sam himself.

Dean's hand rested on Sam's arm, not tight or controlling, but as an intimate, brotherly way of giving comfort, assuring Sam that he was there, and perhaps giving some self-comfort in reminding himself that his little brother was still here, too. Castiel couldn't make out what they were saying, but he also understood that some things –most things, even – belonged between the Winchester brothers and the Winchester brothers alone. Even Bobby, who gave Sam the closest thing he could to a hug as soon as his boy woke up, left a few minutes ago claiming to need a trip to the can, thought it was obvious that he was giving the brothers some time to be alone.

All that was left was Castiel, who was taking his post as guardian seriously, all but glaring at anyone who came two inches too close to the door. It really didn't matter to him if the threat was human or not – the angel had no intention of Sam getting hurt again anytime soon. Dean had to pull him away when a nurse came in to test Sam's stats and he practically threw the horrified-looking young woman against the opposite wall. He was unbelievably lucky, said Bobby, that Castiel still had his ability to erase memories. Castiel was usually never so reckless, and when Dean had to stop him from being too overprotective about Sam, everyone in the vicinity knew that something had changed.

Or maybe nothing had changed, really. Maybe it took seeing Sam in such a helpless state to trigger his already deep-running emotions about him. It was easy to hate the demon-tainted man with smeared blood on his lips, with his shoulders set back with dangerous pride and mouth curled into a dark grin. What Castiel saw in that ally – and what Castiel had seen of Sam since the day the seal fell – was such a contrast, it was stunning. This Sam, the one he knew now, was gentle, thoughtful and sympathetic, but such a strong sense of self-loathing ran through his entire existence, it was almost smothering him. Perhaps that self-loathing was there even as far back as when they met, just hidden behind false power and a need for survival and revenge.

Suddenly, Castiel was startled out of his thoughts by a gentle hand on his shoulder. "You can see him now, Cas."

The angel turned around, starring into Dean's hell-filled eyes which he could cover up most of the time. Now, though, Dean was open, almost vulnerable himself. His calloused hand squeezed the angel's shoulder, giving a very clear message though such a simple gesture: 'thank you'. Castiel gave him a small but rare smile back – 'you're welcome' - deeply touched that Dean trusted him enough to willingly let his guard down in front of him, and a part of him was honored that they knew each other well enough to communicate in the silent ways he had seen Sam and Dean interact.

The angels who abandoned him, lied to him, abused their power so mercilessly on others – they were no longer his family. These humans, these shattered, miniscule existences that he fought for – this was his family now. And the angel found that he didn't regret it.

Castiel walked into the small white room, closing the door behind him. Already, Dean's back was leaning against the window glass, arms crossed and position defensive. Castiel trusted Dean to watch over them for the next few minutes. Instead, he went to sit down next to the overgrown form swathed in bandages and blankets.

When Sam looked up at him, he managed a very weak smile. Not one of true happiness, and that ever-present self-loathing was deeply imbedded into the creases in his grin, seen only by those who knew how to look. One side of his face drooped more than the other, thanks to the tenderness of those bruises, but Castiel could see that he was trying very hard to be sincere. Because that's who Sam was – the one who gave away everything but expected nothing back.

Maybe it was about time that changed.

"Cas," he croaked out, as Castiel sat down in the uncomfortable plastic chair beside the bed. His voice isn't desperate this time he says Castiel's name, but familiar, almost warm.

"Sam," he responded, half-tempted to put his hand on Sam's arm as Dean did, but something told him that he wasn't allowed to try to imitate the brother's relationship, no matter how close he was to either of them.

"I…I remem – just – thanks, Cas." Sam voice grew quieter, but the earnestness of his words didn't fade away. He paused, before continuing: "Dean probably would've gone crazy worrying if you hadn't found me."

Castiel's eyebrows raised at that. "You're welcome Sam," he started, soft and genuine, "but I didn't come just because Dean called. I came because you were in trouble."

Sam bit lip and lowered his eyes. "You don't – didn't have to worry about me –"

"Of course I worried about you, Sam," Castiel intervened, his voice serious but not entirely hard. "You would have done the same for me."

Sam looks a bit surprised at that. "'Course I would, Cas. I just – you're looking for God and…you always come when Dean calls – and I get that you prefer him, it's okay, I get it –"

Now it's Castiel's turn to be surprised. "I come when Dean calls because he's the one who usually calls, Sam, not because I…prefer him over you. My bond with Dean is strong, true. But it concerns me to think that I would ever do you harm." Castiel silenced what would no doubt be Sam's fruitless protests with a look, before continuing. "You need to know that I would never hurt you, Sam. Because even though I do have a bond with Dean –"he looked down, his tone serious but his expression uncommonly soft, "- I feel just as strong a connection with you."

Sam's hazel eyes looked up, and Castiel could see something akin to tears welling up at the edges of them. This immediately alarmed the angel, and he reached out towards his face. "Are you in pain? I can call –"

"No, no, it's – m'fine, Cas," Sam said, swatting his hand away, chuckling wetly. It's a very different reaction from when he tried to touch his face last, and Castiel felt a fire burning in his belly – not one of rage, but a glowing, pleasant tingling sensation – when Sam didn't so much as flinch. "I just always assumed you were – I don't know, Dean's angel. You fell for him, after all."

Castiel considered this for a minute, realizing the truth in Sam's words, but also accepting something much more important.

"I did fall for Dean," Castiel said, placing a hand on his shoulder before Sam's expression could deteriorate. "But I also fight for you."

Suddenly, Sam was rubbing his palms into his eyes - a motion, Castiel noticed, for wiping off and hiding the stronger onslaught of tears. But when they pulled away, Sam was smiling. Not feebly, not for the benefit of someone else, but because he was happy. Castiel had never seen such pure undisturbed joy on his face before. The emotion fit him well, and Castiel was suddenly determined to make sure that Sam smiled like that again, and often.

"Thanks, Cas," he said again, but this time like a man whose burden was lifted off of him, at least for a time. Sam would probably never be rid of the guilt that haunted him – he cared too much, had too a large a heart to do otherwise – but at least now he knew that he had one more hand willing to carry the load.

Castiel could see the sleep behind Sam's eyes. He reached out, smiling, and gently pressed two fingers to his forehead. He couldn't take away his friend's pain, but he could at least help him speed his recovery. "Rest now, Sam," he whispered, as Sam's eyes fluttered shut peacefully.

Long ago, Castiel thought that Dean would be the only one left who would fight for The Boy with the Demon Blood. Castiel knew now how incredibly wrong he was. And he was glad.

Before leaving the room, Castiel stood up, leaned forward, and kissed Sam's forehead. It was the first kiss he'd even given, and the receiver the only one he ever could have wanted to give it to.

It was for Sam.