It started as an uncomfortable itch in his lungs, small but irritating. Quickly though, the feeling pushed its way up his throat and suddenly Dean was awake, coughing violently and feeling his dry lips split.

"Easy there, boy," Bobby's gruff voice sounded towards his right.

He opened his eyes gradually, wincing at the sunlight filtering in through the windows. The tacky, yellow-striped wallpaper and mismatched carpets were a familiar sight; he and Sam had stayed in this motel room for the past four days.

"What happened?" Dean croaked, nearly gagging at the foul taste in his mouth. Jesus Christ, he needed a drink and a toothbrush, the order be damned.

Bobby opened his mouth to reply, but another voice cut across immediately. "You are slightly dehydrated, and lacking in some essential nutrients, I believe."

Dean jerked his head around in surprise at the new voice. He instantly regretted the action; the ensuing dizziness made his stomach churn. "What the hell."

Bobby snorted, reaching over to help the younger man sit up. "Don't look at me, I was gonna ask you the same thing."

A stranger was in the corner of the room, sitting stiffly on a wooden chair Bobby or Sam had dragged over. He was pale, his dark brown hair messy and looking slightly windswept. Dean took in his outfit with confusion: a trench coat over a dark blue two-piece suit. This guy was dressed like a friggin' tax accountant or something.

"Who are you?" He barked as sternly as he could manage. Belatedly, Dean spotted the ring of white powder circling the ground around the chair: salt. "Bobby, what-"

The older hunter pushed a plastic cup full of water into his hands. "Not a freakin' clue," he sighed. "Your brother and I took down the witch and hightailed it back to that warehouse. We found your unconscious ass strapped to a table, covered in blood, and Big Bird here sitting at your feet." Bobby glared hard at the corner. "Wouldn't leave your side for nothin' and damn near knocked us into next week with just a snap of his fingers."

"I apologize for that," the stranger interrupted evenly. "You were armed; I feared further injury to Dean."

Bobby's expression remained unforgiving. "Won't tell us jack squat either."

Dean looked down at the salt again. "How'd you even get him in here?"

"I brought you here," the stranger supplied helpfully. "Your brother indicated that it'd be the wisest course of action." He tilted his head slightly, gazing down at the salt circle. "I mostly agreed with that."

"What-" Dean winced as he sat up again, head throbbing from the motion. "Who are you?"

The man looked a little disappointed, his mouth pulling down into a frown. "You don't remember? I-"

There was a rattle at the door. It opened with a creak and Sam pushed into the room. He carried several plastic grocery bags in one hand and a weathered-looking book in the other. "Dean," he said with visible relief. "You alright?"

"Peachy," he snapped. "Can someone just tell me who this guy is?"

Sam set the bags down on the table, bringing the book over to the bed. "We're not sure yet."

"You're not sure?" Dean leveled sourly.

"We grabbed her grimoire, but it looks like it's written with some sort of cipher." Sam rubbed a hand wearily across his face. "No idea what she was trying to cast or do to you. Give me a couple of days and-"

The stranger sat up straighter. "What information do you require?" Dean noticed that he was looking straight at him with an odd sort of intensity, rather than at Sam or Bobby.

Okay, weird. Not to mention that those somber blue eyes of his were familiar in a way he couldn't place. "Lots, buddy," he snapped. "Like, for starters: who the fuck are you?"

"Castiel," was the immediate reply.

Dean blinked. "What?" What the hell was that word? "You're a cas-"

"My name," he corrected patiently. "Is Castiel."

Sam looked taken aback. "Wait, you'll answer Dean's questions but not ours?"

Castiel shrugged. "I am not bound to either of you." His eyes slid right back to Dean. "Unless you wish me to answer their questions."

Sam could see Dean's face contort in confusion; that sometimes led to unproductive lines of inquiry. He pushed his brother's shoulder firmly, a suspicion niggling at him. "Tell him to answer us."

"Dude." Dean scowled briefly at his brother. Nonetheless, he turned back to Castiel. "Tell em' what they wanna know."

Sam waited a pause. "What are you?"

Castiel folded his hands on his lap. "There are many words for what I am, but most humans refer to my kind as familiars."

Dean, who'd been taking another sip of water, choked. "A what?"

"A familiar," Castiel repeated. "Specifically, your familiar."

This time Dean coughed rather violently, so Sam interceded. "You said you weren't bound to me or Bobby. You're bound to Dean, though?"

"That is correct." He looked mildly concerned at Dean's coughing fit. "The witch you killed was attempting an invocation." At Dean's blank look, he added, "It's a type of summoning ritual."

"Wait a second," Dean said slowly. Splintered memories were all he could recall of the warehouse: smeared blood and cold tables and pain. But there had also been a bright light, striking eyes, and...wings. He turned sharply towards Bobby. "You called him Big Bird."

The other hunter gestured vaguely at Castiel. "He had wings the size of your brother. Gone now, though."

That earned Bobby a patented glare, but Sam turned back to Castiel. "We've met a couple familiars before," he said carefully. "What form do you take? A bird?"

At that, Castiel stiffened. His eyes narrowed, and he looked distinctly offended. The air in the room stirred, and Dean felt a chill suddenly run up his spine. "I am no bird," Castiel grit out, voice low.

"All right, all right," Dean held up a hand. "Calm down, Sammy didn't mean it." He swung his legs over the edge of the bed with a wince. "You're not a bird. So what kind are you?"

Castiel sat up straighter. "We call ourselves the sylphid. But the equivalent in your language would be an air elemental."

Dean didn't react visibly to the announcement, but Sam looked taken aback. "An elemental?"

"The hell's an elemental?"

His brother stood excitedly, hurrying over to the table and flipping open his laptop. "I thought they were legend, for one thing."

"They're supposed to be spirits of nature," Bobby cut in, looking dubiously in Castiel's direction. "Living, breathing elements that walk and talk. No real proof, though. Just some folk tales."

"I assure you I'm not a figment of human imagination," Castiel interrupted calmly.

"If the stories are true, then these aren't things you mess with," Bobby continued. "They pack enough goddamn magic to level towns and whip up tsunamis."

Dean looked Castiel over again. "That witch," he said, brow furrowing in concentration. "She said something about white magic having big guns."

The familiar blinked. "I'm not in possession of any firearms."

"No, I meant-" He stopped. "You know what? Never mind."

"If that witch's spell bound Dean and Castiel together," Sam said slowly. "Then we just need to find one to undo it, right?"

Bobby shrugged. "Sure, in theory. But if you'd have asked me yesterday, I woulda told you there's no such thing as an elemental, much less a spell to send one packin'. You two," he jabbed a finger in both their directions as he moved towards the door and opened it. "Start hittin' the books. I'll make some calls."

An emotion flickered across Castiel's expression, but it was gone before Dean could identify it. Instead, he cleared his throat. "You...wish to undo the binding?" The question was low, hesitant.

The man frowned. "Well, I'm not sure if you've noticed...but I'm not exactly a witch. Uh, wizard?" Dean picked up the cup of water again, draining it in one go. "Whatever. Besides, you said that spell summoned you here. So you've got a home, right? Don't you want to go back?"

Castiel tilted his to the side, the motion oddly bird-like. "I suppose," he eventually said.

Dean rubbed nervously at the back of his neck. "It's nothing personal, dude," he added. The guy looked disappointed and it made guilt curl within Dean. "I- I mean, Sammy and I wouldn't know the first thing about...keeping familiars." He peered over his shoulder, but his brother merely looked amused at the conversation.

"Well," Castiel dropped his gaze. "Human spellcrafting is not an area I have any particular expertise in. But I will offer my assistance however possible." He looked pointedly down at the salt line around his chair.

Dean hesitated, but bent over after a moment and scuffed out several inches of it.

"Thank you." The elemental stood, carefully stepping away from the chair. He glanced around the room, looking vaguely displeased with it. "With your permission, I will stand guard outside."

"Guard?" Dean echoed. "Uh, you don't need to, I mean-"

Castiel narrowed his eyes, confused. "It is my understanding that witches often operate in covens," he persisted. "If such is the case, you ought be be on your guard as you've slain one of their members. This is a necessary precaution if you are not leaving the area immediately."

"Right, okay..." Dean nodded, not a little surprised. "Just, uh...yell if you need anything?" The guy probably meant well, but Dean wasn't sure how he felt about suddenly having a supernatural bodyguard.

Nevertheless, Castiel smiled at his words. "Thank you, Dean. You are a good man."

The older Winchester barely had time to register the abrupt appearance of enormous, raven-black wings before the elemental was gone, disappearing from sight with the sound of rushing wind. "Wow."

Sam cleared his throat, eyes fixed on his computer screen. "So. You have a familiar." He pressed his lips together, holding back a laugh.

His brother shot him an annoyed glare. "Don't you dare start, Sammy." He picked at the pile of clothes stacked at the foot of the bed. "Crap," he sighed, pulling his jacket out by the sleeve. Ragged holes dotted the back, and dried blood crusted a good portion of the fabric. "Christ, is that mine?"

Sam looked up. "I think? There was blood all over the place, but you didn't have a scratch on you when we got there."

Dean blinked, trying to organize his memories. He remembered a knife, recalled the white-hot sensation of it slicing through skin and muscle. He could practically feel it like a phantom pain in his gut. Suspicious, he rolled up the hem of his worn t-shirt.

Nothing. The skin was unblemished, without a trace of any injury. That witch had definitely tossed him against a couple walls, but it sure didn't feel like it. Beyond some general fatigue and slight soreness, Dean felt almost completely normal.

"Castiel said you'd be fine, that you just needed some rest," Sam continued. "Why?"

Shaking his head, Dean grabbed his duffel bag and rummaged around for a change of clothes. "It's nothing," he replied, tugging on a clean jacket. "I'm gonna grab a burger. You want anything?"

His brother shook his head. "You look beat, man. I'll get it for you."

"Nah, it's okay, Dean waved him off. "I need to get some air. Besides, you'd probably just bring me a salad."

Snorting, Sam pushed the keys to the Impala across the table. "It wouldn't hurt. You sure you don't wanna rest?"

"I'm not an invalid, Samantha," his brother huffed, already halfway out the door.

The night air was cold and Dean shivered as he pulled his jacket closer around himself. It was practically deserted in the parking lot, save for a couple cars here and there. The Impala was parked next to Bobby's truck, its black paint glinting softly under the glare of a dim streetlight. He ran a hand along its side fondly before unlocking the door.

"Dean."

"Holy shit!" Dean jerked back in alarm, nearly dropping the keys.

Castiel stood barely six inches away from him, looking slightly affronted at Dean's reaction. "Did I startle you?"

He rolled his eyes. Castiel looked and talked like a person, but the similarities apparently ended there. "Dude, normal people don't just pop in and out of sight like that." He straightened up, opening the car door with more force than necessary.

"My apologies," the elemental murmured, striding over to the passenger side door.

Dean looked askance at him. "What are you doing?"

"Accompanying you." He slid into the seat tentatively, expression dubious. "You humans choose such inefficient means of transportation."

"Whoa, whoa, whoa," Dean spluttered. "One, don't call my baby inefficient. Two, you ain't comin' with me."

Castiel was not so easily deterred. "It would be extremely remiss of me to neglect your safety, Dean." He pulled curiously at the seat belt. "Especially after taking the time to save your life in the first place."

Dean frowned, sliding the key into the ignition. "Did that witch stab me? Or was I imagining things?"

The other man nodded. "Yes, that did happen. It was fortuitous that I arrived in time to heal you."

"You can heal people?" The hunter's eyebrows shot up.

"Not exactly," Castiel answered. He traced a finger over the air vents, looking mildly interested. "Technically, I transferred a measure of my powers into your body." He turned back in Dean's direction. "The temporary influx of magic allowed you to recover beyond your normal capacity."

"Okay...I'll take your word for it," Dean sighed. He finally turned the key, listening to the rumble of the Impala's engine. Automatically, he reached to flip on the radio. Dean hesitated though, looking sidelong at his passenger. "Thanks," he managed. "You know. For saving me."

The smile Castiel gave him was startlingly wide. "Of course."

Turning away, he pulled the Impala out of the lot. He took a left once they reached the main road; they'd passed a sleepy-looking diner on the way into town. It was awkwardly quiet as they drove, and Dean somewhat regretted not turning the radio on right away.

Castiel was unperturbed, though. He peered out the window with detached interest, hands folded in his lap. "The world has changed much over the centuries."

"Centuries?" Dean echoed. "Dude, how old are you?"

"About a thousand of your years, I believe," the man replied. "My kind does not track the passage of time as avidly as yours does."

Dean didn't bother masking the disbelief that was definitely on his face. "You've been around for a thousand years and no one's ever spotted any of you?"

"Longer, actually. I am not as old as some of my fellow elementals." Castiel leaned back against the seat. "We do not usually exist in a physical form like this," he explained, gesturing down at himself. "Your friend was not incorrect to call us spirits."

"So, you're like ghosts."

"No, Dean," Castiel's brow furrowed. "There is magic in every aspect of life, be it large or small. You will find it in the wind, in the water, in the Earth. And though mankind might not realize it, it is all alive." He held up a hand, flicking a finger idly. For a moment, the air around them grew chillingly cold, then warmed up again. "An elemental has not walked amongst man in a very long time. I am not surprised that we have become mere stories to you."

The hunter looked his passenger up and down critically. "Why? What stopped you?"

"Natural magic is inherently good, Dean. When real evil walked the Earth, my kind sided with humans to help dispatch of it. Man learned to craft spells and to fight the creatures of darkness." Pausing, Castiel sighed. "But as the decades passed, some of the wizards and witches were aligned ourselves with became greedy. They sought to use our power for personal gain." He turned away. "War broke out. Man fought over petty issues."

Dean looked skeptical. "So you guys ran."

The familiar turned back sharply, eyes narrowed. "We withdrew," he corrected stiffly. "The affairs of humankind were not our concern."

"Maybe. But there's still evil stompin' around," Dean countered. "You guys don't feel like jumping in for that?"

"Where there is light, there will also be darkness," Castiel returned neutrally. "It was necessary for humans to learn to fend for themselves."

"Yeah? So what changed?" Looking ahead, he spotted the diner in the distance. "Why come down to save my ass?"

Castiel was silent for almost a minute, gazing placidly towards the horizon. "It's difficult to explain," he said cryptically.

"What? You get bored floating around or something?" The rumble of the engine died down as he turned the car off.

"No, Dean," the elemental tilted his head, looking perplexed by the question. "I merely thought you deserved to be saved. Is that so hard to believe?"