Hey guys! I'm back :) Thanks for your patience, I haven't had a lot of time to write lately so this one took me longer than I expected. However I hope you enjoy this, because I had a lot of fun writing it. I've wanted to do a Cas and Crowley story for a long time and I finally got around to it!

This is set in Season 12 sometime after "The Foundry"

The Best of All Possible Worlds

A Supernatural Fanfic

Chapter One

The vehicle they were riding in hit a bump, throwing Castiel to one side, sending him practically into the lap of the demon next to him, both of them unable to catch themselves because of the chains locked tight around their wrists and ankles.

"I hate you," Castiel seethed.

"For the last time, you cannot blame me solely for this," Crowley growled back, shouldering Castiel's aside so that the angel was not invading his personal space quite so much. "You were the one who attacked first."

"You were the one who said your contact was to be trusted."

"I said I trusted his information, not him, there's a difference. I'm not in the habit of trusting anyone." Crowley rolled his eyes. "I'm usually better at getting out of these situations unless I'm attached at the hip to a feathered idiot who has decided the best tactic is shoot first ask questions later."

"So you're blaming me now?" Castiel demanded.

"I'm just stating the facts, darling," Crowley shrugged.

Castiel rolled his eyes and slumped back against the side of the van. "I hate you," he muttered again. It sounded more petulant than anything, but he couldn't be bothered to care at the moment.

This whole day had just gone from bad to worse. Castiel had been working with Crowley for weeks now, tracking down Lucifer. That was enough to make anyone want to smite themselves, but the fact that Crowley wanted to make this a 'buddy comedy' as Dean said, instead of just a business relationship made it even worse. The demon would simply not shut up. Whenever Castiel tried to get a few minutes alone to gather himself or check in with Sam and Dean, Crowley was right there at his elbow. It was getting infuriating.

And this had been the last straw. Crowley had gotten word through his channels of information that a contact of his knew where Lucifer was hiding out. Castiel had been wary, but they had no other leads and Rowena hadn't been able to find anything either, so they had to take the chance.

And it had turned out just as bad as Castiel expected. Not two minutes into the meeting, the contact had sent his lackeys out to secure Castiel and Crowley. Castiel was done playing games and simply attacked the contact before he or his men could take Castiel and Crowley out.

However, that had backfired heavily, leading to the lackeys taking precautions and Castiel and Crowley flat on the floor in sigiled handcuffs, blades pointed threateningly at them if they made a move. Crowley blamed Castiel for the preemptive move, but really, Castiel had just delayed the inevitable. The contact had been too quick on the draw to not have planned the trap from the beginning. Crowley should understand that you couldn't always just talk your way out of something—or disappear when that failed to work.

So now that led them to their current predicament. Someone had showed up soon after their capture to load them into this vehicle and drive them off to who knows where. Castiel feared that it would be to Lucifer himself. That would just be their luck.

The vehicle came to a stop and Castiel glanced over at Crowley, seeing the demon do the same.

"Well, for the record, it was nice knowing you," Crowley said as the back of the vehicle was opened and light flooded in.

Castiel tensed, hating feeling so vulnerable. One of the men—a demon—climbed in and grabbed Castiel by the shoulder.

"Get up. And don't make any funny moves or you'll regret it," he snarled.

Castiel glowered at the demon but had little choice but to move forward and stumble out of the vehicle. It was better than being dragged out and landing on his face.

Crowley came next, growling. "Watch the suit, it's Armani!" he snapped.

"That will be the least of your troubles soon," said another of their captors before they were sandwiched on either side and ushered into the building the vehicle had parked next to.

As they were hauled inside, Castiel looked around warily. The place looked like it might have once been a warehouse or factory but as they were taken further, Castiel began to feel warding pressing down on him, more than just from his cuffs. He began to have even worse feelings about this situation than he already had.

His fears were proven to be appropriate as they were taken down a flight of stairs and came out into a large room that had cages lined up in rows covering the whole area. In most of the cages, there were men and women, crouched, some hollow-eyed and dejected, and others snarling and furious.

But not just men and women, Castiel realized. All of them were supernatural creatures of some kind. Vampires, werewolves, djinn, witches, even a few other demons. The only sure thing was that there was not a human in the bunch.

"Bloody hell," Crowley murmured.

"Get moving!"

Castiel was shoved roughly in the back, not having realized he'd stopped to stare, but he stumbled forward and the men continued dragging him and Crowley through the room, between the cages.

The prisoners hissed and rattled their bars as they saw them, most sneering in derision that someone else was likely about to share their fate, and others crying out for help. Castiel glanced down and saw a young girl, a werewolf, he thought, reaching through the bars toward him, a pleading look on her face.

He forced himself to look away as he was dragged forward. There was nothing he could do in his current situation.

There was a door at the other side of the room that led to an office and a guard standing there. He nodded to the escort guards and opened the door as Crowley and Castiel were pushed inside.

In the office, a man sat behind a desk, talking to another man, writing something in a ledger, but he looked up as the captives were brought in and nodded to the men.

"These the new acquisitions?" he asked.

Crowley's cheeks puffed in fury. "Acquisitions? Do you know who I am? I'm—"

One of the guards flanking him whipped out a stick that looked like some kind of cattle prod and jabbed it into Crowley's lower back. The demon cried out and staggered forward a step, nearly collapsing.

"You speak when spoken too," the man said, standing up and straightening his suit. He was tall and broad and towered over Castiel and Crowley both. He was a demon too, like the guards, but Castiel noticed that the other man in the office was a vampire. He frowned. It seemed he might be wrong about this being connected to Lucifer after all, as this demon was obviously in authority here. So if this wasn't about Lucifer, then what was it?

"What do you want with us?" Castiel demanded.

One of the men flanking him had a stick like the one Crowley had been shocked with and he shifted angrily. Castiel braced for the pain but the man in charge waved the other demon off.

"You'll find out in good time." He stepped forward and looked Castiel up and down, making him uncomfortable. The demon's eyes widened slightly. "An angel. Well, this is a surprise. A rare find. Odd to find one hanging around such company, but then I suppose the King of Hell never did discriminate from the filth."

Crowley opened his mouth to retort but Castiel shot him a look. It was best not to make this worse than it already was until they found out what was really going on.

The demon leader stepped over to Crowley and gripped his chin, wrenching his head back and forth. "The deposed, disgraced King of Hell isn't worth much, granted. But someone may pay something to have him as a novelty item."

"Novelty item? Excuse me?" Crowley practically shrieked.

The demon backhanded him across the face, a smug smile appearing on his lips, obviously enjoying the situation. "You'll learn your place. Until then remember that you're my property now." He turned to Castiel and the angel met his eyes darkly. The demon tried to stare him down, then nodded to his guards who each grabbed Castiel's arms, holding him tight.

"The angel on the other hand…you'll fetch a pretty price, sure enough. Your kind are much sought after by our clients but you're hard to get ahold of. Last angel came through here got me more than the rest of the sales combined." He smirked and reached out to grip Castiel's chin, wrenching his head up. "And you're prettier than the last one too."

Castiel's lip curled and he pulled out of the demon's grasp. The demon seemed to be done with them though, turning around and returning to his desk. "Get them settled in. We only have until tonight and the clients will start showing up in a few hours." He glanced over his shoulder at one of his men. "Oh, and make sure they know what will happen if they try anything foolish."

Castiel and Crowley were hauled from the office and toward another door. Castiel still didn't know what to make of this. They were obviously to be sold, but why? Who was in the market for supernatural creatures?

They were taken to another room, this one stark and mostly unfurnished. Castiel and Crowley were shoved to one side and their manacles were unlocked briefly. They were stripped to only their shirts and trousers—Crowley protested enough to be shocked again—and the guards did another, more thorough, search for hidden weaponry. Their manacles were then looped around a solid bar attached to the wall and locked once more, their hands now in front of them as they faced the concrete wall.

"Bastards," Crowley muttered under his breath.

Castiel was inclined to agree.

The guards stood off to one side as another man approached them. A vampire, Castiel noticed, who grabbed Castiel by the chin and wrenched his head around like the demon had. Castiel was getting really tired of being manhandled. An assistant came over with a clipboard and pen, ready to write things down.

"Angel?" the vampire asked, raising an eyebrow as he poked and prodded Castiel, inspecting his muscles. "Nice specimen. Good meatsuit." He pried the angel's jaw open and looked at his teeth. Castiel pulled back, furious, and the vampire pressed his lips together into a flat line. "Spirited. But that's nothing that can't be fixed."

He nodded to his assistant who had been jotting notes this whole time and the man handed him a small metal disc. The vampire stepped back over to Castiel and grabbed his chin again. Castiel tried to struggle as the vampire brought the small disc toward him, but he was unable to stop it from being pressed to the side of his neck. Castiel felt something pierce his skin and he inhaled sharply as the metal disc adhered to his flesh. He could feel sigils activating on it, tamping down his grace just like the manacles were doing.

"Now let's see those wings, angel," the vampire said.

Castiel stiffened, furious. "Bite me," he growled.

The vampire pulled out a small remote from his pocket and pressed a button. The metal disc in Castiel's neck burned and sent a shock through his entire body, making him weak at the knees. He slumped against the wall, panting. The vampire pressed the button again and Castiel was unable to keep from screaming.

The vampire finally stopped the torment and reached out to yank open Castiel's shirt, shoving it down his shoulders to hang at his elbows. "I said show me your wings." He commanded.

Castiel gritted his teeth but refused. Another shock tore through him and it was everything he could do to keep his feet.

"Do as I say, angel or your demonic friend will get the same treatment," the vampire said.

Castiel huffed and glanced over at Crowley. He would be amused they were assumed to be friends, if their situation wasn't so dire.

"For Hell's sake, Castiel, stop being so damn proud," Crowley snapped.

Castiel sneered but Crowley was actually right. He'd either bite his pride or end up unconscious on the floor and he couldn't afford that, not when they needed to look for any chance to escape. He bit his lip and straightened up, closing his eyes as he forced his wings out of the ethereal plane.

He ignored Crowley's interested staring, and flinched as the vampire gripped one of his wings, moving it around, opening it completely. Castiel bit back a groan of pain. His wings weren't exactly in the best condition considering everything he'd gone through in the last few years and touching them hurt.

"Wings could be in better condition. Make note of that—it's certainly not going to please a collector."

Castiel seethed at this and forced himself to endure the unwanted touching until the vampire finally released his wings and stepped over to Crowley. Castiel made his wings invisible again and slumped against the wall, trembling with the residual shock to his nerves from the device in his neck.

The vampire 'inspected' Crowley much the same and attached one of the metal discs to his neck too.

Once that was over the vampire nodded to the guards. "We're done here. Secure them."

Castiel and Crowley were unlocked from the pole and led back out into the large room with all the cages. They were dragged down one of the rows until empty cages appeared and then those were opened and they were shoved inside. The guards at least unlocked their manacles first but Castiel didn't think this meant much, especially when one of the guards stepped forward with a cruel smile on his face.

"And just in case you two are thinking of trying to escape. Don't." Castiel just then realized he had one of those remotes in his hand and he pressed the button.

Both Castiel and Crowley cried out, dropping to the ground as the electricity tore through them. The guard held the button for what seemed like an eternity before it stopped and he walked off, chucking with the other guards.

Castiel panted, forcing himself into a sitting position and leaning back against one side of the small cage. There wasn't enough room to stand up or lie down, and the floor underneath was dirty with stains he'd rather not think about.

He tugged his shirt back around him, buttoning it with trembling hands as Crowley rattled the door to his cage a couple times before giving up.

"I should have known teaming up with you would be a bad idea," the demon muttered. "When I work on my own, I'm fine, but you, Castiel, you have a way of attracting trouble."

Castiel rolled his eyes. "You can hardly blame me for this since it was your contact." He sighed and leaned against the bars. "I suppose it could be worse. It could have been Lucifer who captured us."

"Oh yes, 'all is for the best in the best of all possible worlds'?" Crowley quipped.

Castiel squinted, confused.

Crowley rolled his eyes. "Voltaire, darling."

Castiel shook his head, looking around the room. "Did you know about this…business… at all?"

Crowley glowered, looking offended. "Did I know about it? No! I'm more into loyal subjects than slavery, Castiel, give me at least a little credit. What we do know is that it has nothing to do with Lucifer so we're, once again, wasting our time, and now it looks like the only way we're getting out of here is being sold like prize stallions! And you are so much more an old gelding."

"Well, we can't do anything about it now, so we should just try and concentrate on finding a way to escape." Castiel looked around as he said it, searching for anything in or near his cage that he could use to pick the lock. He would have to do it the hard way since his grace was completely locked down, but Dean had taught him the fundamentals and he thought that he could manage well enough.

"This is utterly ridiculous," Crowley grumbled. "I'm the bloody King of Hell!"

Castiel rolled his eyes again. "I think they've given up caring about that a long time ago. It's certainly not going to help you here."

"If you're laboring under the delusion that your plaid-wearing boyfriends are going to come save the day then you're wrong."

Castiel grunted. "I don't need Sam and Dean to save me."

Crowley raised an eyebrow. "Oh? History tells differently."

"Shut up," Castiel growled. "I didn't choose to be stuck here with you either, but that's just how it happened. The least you can do is help me figure out how to get out of here. Without using your 'position' and 'power' to do so."

"I sense heavy sarcasm, Cas. I thought we were besties."

Castiel sighed heavily and lowered his face into his hands, just wishing the demon would—or could—go away. He never should have teamed up with Crowley. If he hadn't he wouldn't have been in this mess.

The hours dragged by, however, and Castiel got no further in figuring out a possible way to escape. Crowley was no help either, simply sitting and sulking in one corner of his cage. Castiel suppressed a sigh. It's not that he would wish this situation on the Winchesters—in fact, he was glad that for once they hadn't been roped into one of his own problems—but he would be lying if he said he wouldn't much prefer the company of his friends in a situation like this. At least they would be actively trying to figure out an escape plan.

He still hadn't figured anything out by the time the doors opened into the large room again and guards started to come in and open the cages, dragging the occupants from them. Castiel and Crowley edged closer to the side of their own cages to watch.

"What are they doing?" Castiel asked.

Crowley shook his head. "Haven't the foggiest. Let's just hope we're not next."

It seemed that they still wouldn't have any manner of luck however, because no sooner had Crowley said that then several guards strode toward them. A couple of the cages around them were opened and then guards stopped in front of Castiel and Crowley's prisons.

"Don't try anything funny, you won't get far," one of the guards grunted, another standing off to one side with a remote that activated the discs attached to them.

Castiel glowered at them as the door to his cage was opened and the guard motioned impatiently for him to get out. Castiel rose cautiously and more manacles were secured around his wrists, this time in front of him. Crowley spat several protests, and got a punch to the stomach for his trouble before the manacles were snapped around his own wrists. They were then marched out of the large room with the other freed captives and into a smaller, darker room where the demon who Castiel had assumed was the head of the operation earlier stood with his assistant.

"That should be enough," he called to the guards after they brought Castiel and Crowley in. "We've got a good batch tonight, boys." He looked at his watch and motioned to his assistant. "It's time, let's go greet the crowd."

The assistant followed him out of the room and the guards started getting the captives into a line. Castiel noticed there was a theme: first in line were werewolves, then vampires, then a couple demons, and other assorted supernatural creatures. He and Crowley however, were at the back. Castiel wasn't sure if that was good or bad.

He looked around the room, seeing if there was a possibility of escape, but there were guards flanking both him and Crowley. One of them may be able to escape if the other distracted the guards, but…well, Castiel had told Crowley he would be the demon's partner on this mission. And as much as the King of Hell annoyed him, he also had a sense of loyalty that he could not quite shake. He wasn't going to get out of here without the demon in tow.

The vampire assistant appeared at the door and motioned to the guards. They ushered the werewolves out the door and it shut again. The same was repeated with the vampires, and then the rest of the captives until it was only Castiel and Crowley left.

"Well, they did save the best for last," the demon muttered to him as they stood there awkwardly, glancing around them. "Don't suppose you want to make a run for it?"

Castiel bit his lip, considering it, until the assistant reappeared and nodded to the guards. "Bring the final two."

The guards seized Castiel and Crowley by the arms and hustled them out the door. Castiel stumbled out onto some kind of platform, the guard giving him a firm shove in the back.

At first he couldn't see anything, there were lights shining directly at them, obscuring the rest of the room but as he raised his manacled hands to shield them, he saw a crowd of people waiting eagerly, straining to see what had just showed up, the murmur of interested voices washing over them.

"Ladies and gentlemen, this is the final lot of the night, but we've saved the best for last," the demon in charge said, stepping out to where Castiel could see him, hands spread. "We have here for you…an angel!"

Exclamations burst over the crowd, sounding too excited for Castiel's liking. He tried to shrink back, but there was a guard behind him.

"And another rare gem…the former King of Hell!"

Shock and jeers exploded from the crowd and Crowley fumed. The demon in charge laughed and held up his hands.

"Okay, okay, and now to business. Let's open the bidding!"

The crowd cheered and Castiel's eyes widened, full realization of what was going on here finally hitting him.

"Bollocks," Crowley muttered.

Castiel thought, for once, he had to agree.