Author's Note:

I wanted to thank you guys so much for the support so far. It's been a really strong motivator and I'm very grateful, I hope I don't disappoint :)

The lighting inside was dim as the fluorescents slowly warmed up to full strength, the first thing Dean saw was a pedestal next to the door and massive glass walls on either side. There were different buttons, one of which covered by another lock labeled 'Euthanize.' Another said 'open,' and the last read 'feed' and Dean knew that whatever was in the glass enclosure was an animal of some kind. He kept walking on the metal grating floor, his stomach starting to tighten. The path felt like a catwalk above a theatre stage, it made him feel nauseous. Dean placed his hand against the glass to his right as he passed, it was the closest thing he had to a railing.

In seconds something rushed to his hand, pressed against the wall was a flat-faced figure he couldn't place. It was hunched forward and almost resembled a gorilla in body though its skin was scaled like a lizard. It was startling, he didn't expect it and its face was so strange. It had a wide mouth, small nose, and docile, dark eyes that didn't help the creepiness of its presence. The glass was so thick the creature looked like it was two feet away from his hand, Dean couldn't hold back the sigh of relief that escaped him when he noticed that.

"Sammy!" he called and picked up his pace, Sam had like a 30 second head start, how far could he have gone? "It's really weird in here, let's go back!" There was no answer, Sam was either in danger or sound didn't carry too well in that place. Dean prayed for the latter.

The path split just ahead, three directions to go and Dean had no idea which one Sam would have chosen.

"SAM!" Still no answer. "Goddamn it," Dean growled and 'eeny meeny miny moe'd his way through it, going straight ahead.

There were many more pens encased in thick glass, each with its own environment. Some were left with the cold metal flooring and dim lights while others were given some dirt flooring. It kinda differed based on what sort of animal they resembled, or at least he figured that was why. They were the things he'd seen on the monitors, he passed the rabbit-dog thing and noticed just how rabid the thing was. Some were so quiet and others vicious. He didn't dare linger too long to stare at the things; Sam was in there somewhere. He'd noticed that he could hear the creatures pretty well; some of them pounded against the glass others just made loud, howling-like noises. Which all meant that Sam should've been able to hear him but didn't respond. It also meant he'd probably hear if Sam were in trouble, which just made him wonder where the fuck his brother ran off to.

The path went down further along and Dean regretted picking the way he had, but he couldn't turn back now. He continued down until the floor was made of cement and he could smell earthier than metallic scents. As he continued forward he noticed that the area was far more open than above, subconsciously Dean knew that Sam wouldn't have gone this way.

It was quieter down there, he couldn't hear any machines, no creatures were hitting thick glass, nothing but his own footsteps. Dean's nerves were starting to get the better of him, there were obvious science experiments around him and he knew by the cameras that at least one was human. His skin prickled and hair stood up on his neck, signs he knew he should take as 'get the fuck out of here' but his curiosity lied to him with the same line; Sam might be down here. The scarier it was the more he was certain of it, Sam had a nasty habit of getting into the worst situations.

Dean wasn't an idiot though; he knew that it was far too real a possibility to get lost in the labyrinth that he found himself in. Turning back at that moment meant going in one straight direction, but he noticed something further ahead.

There was a light, it was bright and lit up the entire hall around it. Dean walked closer to it, drawn like a moth. Into view came a dome, it took up an enormous amount of space – almost as much as the first room by the look of it. The most impressive part was how high up it went, the peak of it must have hit the same level as the ceiling in the other room too; despite the many stairs that they had descended initially.

The closer he came the more he could see how unique it was; the other enclosures didn't have anything to identify them other than the creature but this one had a label above the door.

"Castiel?" he read aloud and looked inside, it was such a strange space. There was a sort of den, or a burrow. It was carved into the earth; the rest of the floor was put in around it. The lighting above it was warm, incandescent; Dean wondered why there was a difference since everything else was washed in a cold white.

Nothing moved inside, but he could see something that made his stomach turn; a set of human legs. They were extended from inside the den, completely still and lifeless as far as Dean could tell. A human inside a glass cage, he couldn't imagine what this person had gone through. How long had it been since someone fed them? Were they dead?

Against better judgment and self-preservation he reached over to the pedestal with the same buttons as the other closed areas. He hesitated, fingers just above the 'open' labeled option. Nothing made a sound inside, he was pretty sure of it. There wasn't anything moving.

Dean clenched his jaw and pushed it, the sound of air rushed by and an unfamiliar scent hit his nose. The first thing that happened inside was the retraction of the legs, whoever was in there was definitely alive. Dean cleared his throat and slowly inched closer; stepping inside the dome he spoke softly, "Hello?"

Quick and heavy breathing was the initial response accompanied by a quiet grunt, Dean stalled where he was and waited. He wasn't sure he wanted to get much closer, but the person sounded scared so he figured not moving would be his best option. Similar groans left the den, Dean couldn't see the person inside but he knew they were there.

It was a few moments of the same rapid breathing and various panicked sounds before Dean tried to make himself look smaller, "It's okay, I'm here to get you out." He kept his tone as non-threatening as possible, still questioning whether or not he wanted this person to come closer.

Before he could make up his mind on the subject a young man's face peered out of the den's entrance. Dark, messy hair only made it clearer that the man hadn't seen sunlight in far too long. But that wasn't what caught Dean's attention, the way the light caught the captive's eyes made them glow an almost blinding blue. It was unnatural but beautiful; Dean couldn't help but wonder what made them do that.

"Hi," Dean smiled and gave a short wave, "you can come out, it's alright."

The stranger slowly leaned forward until he started to crawl out; each move was careful and hesitant but he never broke eye contact. Dean smiled and watched the young man come out into the light, though the more he saw the wider his eyes got. There was a massive deformity on the guy's back; it was white and kinda fuzzy

Dean's focus on the abnormality was cut short as the stranger's pace increased. It crawled quickly toward him, never getting up from the ground and scaring the shit out of him. Dean let out a sharp cry when unfamiliar hands grasped onto his legs and yanked him down. He hit the ground, flat on his back with the wind knocked out of him. Dean gasped but couldn't quite catch his breath before the bright-eyed male perched over him. The malformation on its back spread out and arched over the both of them; it was then that Dean realized it wasn't some strange fuzzy lump but feathered wings, beautiful and a bit dirty from living in a burrow.

His heart was racing as he stared up at the glowing blue, unreadable to him in his fear. The winged man's face was intense but neutral, if there was malicious intent it was well hidden. Dean didn't know what this guy was thinking, what he wanted or if he was even as human as he looked, but Dean knew he had to do something. His gut told him he wasn't safe, not yet. One wrong move and he'd probably lose his head to this experiment.

"Uh," Dean uttered a sound, it wasn't strong but it was enough to be heard. He took a slow breath to try and relax, a forced and anxious smile on his lips. "Hi there, what's your name?"

The stranger didn't answer with words; instead there was a soft whine from the back of his throat. His expression didn't change though, so Dean continued trying.

"Well I'm Dean," he made sure to speak gently, aggression from his position would result in the loss of his head, he was pretty sure of that. "It says something outside above the door, is that your name?" No reply and no movement prompted Dean to continue, "Castiel?"

The second the name slipped into the air between them the stranger lit up, his eyes widened and a small gasp escaped him. Dean smiled; it was possibly the cutest sound he'd heard.

"Castiel, huh?" he repeated and got another little grunt, "It's a nice name, can you talk?"

Castiel didn't respond, his wings folded onto his back again and he sat down on top of Dean. It was then that Dean realized the guy was naked, it made more sense that he didn't have clothes but it was still not something Dean anticipated happening to him that day. He tried to focus on Castiel's softened expression, noticing that the sharpness of that odd glow in Castiel's eyes had disappeared.

Dean reached up slowly to see if he could touch Castiel's face but the young man's eyes flashed bright again and moved away from his hand. Dean lowered it back down though not before Castiel could smack at it and knock it back to the ground. Dean decided to remain still for a little while longer; maybe Castiel would relax or get bored of sitting on him.

They sat that way for several minutes; Castiel staring at Dean intensely while Dean laid flat on the dirt floor silently praying he got out with his life intact. He started to question why he even walked inside the enclosure in the first place. It was a stupid move but he'd done it. Would he have opened a door to a teeth-gnashing monster like in the other cages? Probably not. So why this one? Because it had human legs inside, that's why. And, as an added bonus, Dean Winchester was also an optimistic moron.

He sighed and closed his eyes, figuring maybe Castiel functioned like some animals that were threatened by prolonged eye contact. It could've also meant the end of him since he just let a strange experiment out of his sight, but again, Dean was an optimist.

Forever passed by, the warmth of Castiel on his abdomen hadn't lifted, nor had the weight. Dean peeked an eye open and Castiel's wings perked up as he suddenly watched Dean more intently. Nothing from Castiel was angry or fearful, just curious little flutters of his feathers and a nearly inaudible hum from his vocal chords.

Dean smiled and closed his eye again. He felt Castiel shift a little and noticed a shadow over his face. Before he did anything to react he felt a hand on his face and a finger pushing very gently at his eyelid. Dean stifled a laugh but he still scoffed lightly, the sound of which startled his curious wingman.

Castiel squawked indignantly and very suddenly leapt away, his wings ruffled up and batting the air in irritation. Dean opened his eyes again to look but didn't sit up; he didn't want to scare Castiel too much.

As soon as he looked up, though, Castiel was already scampering back to him and crawled right back on top of him, one leg on either side of his torso. Dean groaned at the sudden returned weight, Castiel hadn't sat down gently and went right back to touching his face.

"Okay," Dean sighed with a laugh, giving in to his fate. As he waited for Castiel to tire of his face Dean heard the loud grumbling of a stomach. At first he thought it might be his own but the look on Castiel's face told him otherwise.

Castiel placed his hands over his belly as if he just remembered he was hungry, the whimpering sound he made was too much for Dean. The kinds of noises that came out of him were all sounds humans could make but most people never did. It was uncomfortable to hear them for someone who didn't normally get to.

"You want food Cas?" Dean tried to sit up, his movement not enough to frighten Castiel away this time. He remembered the button 'feed' outside; since MacLeod had died he probably hadn't had anyone hit that button. Everything inside the labyrinth was probably starving. "I've got an idea, c'mon." He wriggled his legs free from underneath his new friend and climbed up to his feet.

Castiel sat on the ground and watched him for a few seconds before getting up to his feet and following Dean's steps all the way to the door. Dean walked right out and over to the pedestal, he glanced back and saw Cas waiting by the exit, he hadn't stepped out and stared at Dean intensely. Cas' gaze went back and forth from Dean to the strange floor just beyond his feet.

"It's okay, you come over here." Dean gestured to try and wave Cas closer, but it didn't do much good. Castiel stared at the floor and paced around on the dirt he knew. Dean smiled and pressed the button; as soon as he had part of the floor in the back of the pen opened up.

Castiel ran to wait for it, perched close to the opening and waiting with an antsy shuffle left and right every few seconds. A platform lifted up but nothing was on it, Dean frowned as he watched Cas circle the area looking for his food. Whatever was supposed to be there hadn't been restocked, MacLeod must not have had time before he bit it.

Though Dean had several questions about the processes the weird facility had, he knew that feeding Cas was would have to take priority. "Cas, c'mere." He called but Castiel was fiercely searching for his dinner.

It took a few seconds before he started to get distressed about the lack of food and a high-pitched whine rose in volume. Cas looked up at Dean with tearful eyes as the platform slowly lowered away again, the floor closed up again as well. Dean felt like he'd just kicked a puppy.

Castiel hurried to the exit and stalled at the door again, pacing again like an animal unsure of linoleum or tiled flooring. Cas stepped over the threshold and pulled back with a squeak. This behaviour continued for a few moments until he crouched low and slowly inched closer to Dean and the pedestal, reaching out slowly.

"There you go," Dean reached down to take Cas' extended hand but Castiel avoided him and instead smacked at the buttons on the pedestal. He knew that food happened when those buttons were hit, though he hadn't read them and accidentally closed his cage. Cas tried to rush back in but was stopped by the reinforced door. He cried out loudly and clawed at it before he flew up and crawled over it. Dean watched in shocked silence as Cas stopped at the very top of the dome and pressed his face against it.

"Cas, it's okay." Dean called to him, trying to be reassuring to this strange human experiment, "Here, I've got a granola bar," he fished in his pocket for the somewhat crushed emergency snack. Dean waved it in the air to try and get Cas' attention, "Cas look, it's food!"

Castiel peered down at him as he unwrapped it, the smell drew him closer until he flew down and landed next to Dean. It was a heavy landing and a little startling but Dean only jumped a little. Cas leaned in close to the granola bar as he sniffed it, cautious of new food. He glanced at Dean then at the bar a few times in quick succession before he snatched it out of Dean's hand. He moved a few feet away and started stuffing it into his mouth.

Dean waited as Cas scarfed it down, a smile almost permanently on his face. He had no idea what the fuck was going on but he felt really good about helping. Cas finished the bar in very short time; he made a hasty return to Dean's side and moved right into his personal space, nuzzling his face roughly.

It was unexpected but Dean welcomed the gesture anyway, Castiel was so primal and affection required physical contact. Dean would've been lying if he'd said he fully saw Cas as a human, he wasn't sure if Castiel had the mind of a man anymore or if he was some kind of animal hybrid. And if Cas was a hybrid Dean wasn't sure what kinds of animals were in him, but at least he was friendly.

"Let's get you something more to eat," Dean took Cas' hand with no protest from his new friend, but as Dean started to lead Castiel to the stairs Cas pulled his hand away. Instead of running, though, he moved behind and held onto Dean's shoulders, using Dean as a mobile hiding place. "Alright, alright, have it your way."

"Dean!" He heard the distant yelling and breathed a sigh of relief; Sam was looking for him.

"Sammy!" Dean shouted back, "Keep yelling, I'm on my way!"