A/N: Okay, there is going to be major heartache, major feels, and major fluff in this fic. You have been warned.

Disclaimer: The boys aren't mine. HUGE thank you to Miyth and 29Pieces for supporting this story, talking things out, and generally just helping ignite and sharing my own excitement for it. :)

Chapter 1

"And that is how you replace the serpentine belt," Dean said, straightening from under the hood of the Continental. He grabbed a rag off the tool cart to wipe his hands.

Cas was studying the engine compartment carefully. "Also known as the drive belt?" he checked.

Dean beamed. "Exactly." At this rate, he'd turn Cas into a grease monkey in no time. The angel's overly analytical brain could be annoying sometimes, but it served Cas rather well when it came to gears and stuff. "That one should be good for 50,000 miles."

He tossed the rag back and pushed the hood down with a thud and click. It'd only been two weeks since they'd saved the world and locked the Darkness away forever, and they'd all taken some well-earned R&R. Which for Dean included having Cas's wrecked car towed to the bunker where he could work on fixing it up. And he'd been teaching the angel how to maintain it. Sure, Dean may have thought the Continental Mark V was a piece of crap, but Cas seemed to love that car, so Dean would help him keep it in good shape.

Cas walked over to the Henley where he'd draped his trench coat and suit jacket, even though he hadn't actually gotten his hands dirty this time around.

"Dean," he said seriously. "Thank you for salvaging the car. I know I told you I didn't care about it, but I am grateful."

Dean shrugged the sentiment off in discomfort. "That's what friends do."

He hadn't taken it to heart when Cas had said that. Ryn had been sick and dying at the time, and Dean taking the time to make sure the Continental wasn't sent to the scrap heap probably had seemed trivial and a touch callous. But Dean had stolidly maintained that once Ryn was better—because they would save her—that Cas would then want his car.

Dean was happy to have been right—on both counts.

Cas slipped his coat back on and swept his gaze over the sharp angles of the car's surface, dented in places from when the Darkness had thrashed it against a bridge. "When will it be finished?" he asked.

Dean rolled his eyes to the ceiling at how quickly gratitude could become impatience. "What's the hurry? What, you tired of hanging in the garage with me?" He never would have thought cars were something he and Cas could bond over, and he'd actually been enjoying it more than he thought he would.

"No, of course not," Cas said hurriedly. "It's just that Ryn has been away from her cabin for a while now, and all her things are there."

Dean's hands stilled over the tools he'd been straightening. Oh. He couldn't deny he was feeling slightly confused; he thought things had been going well with the four of them in the bunker. But maybe Ryn had decided it was too crowded after all. Maybe the two of them just wanted some alone time, and they'd be back later.

"Um, Dean?" Cas asked hesitantly. "It is still okay for Ryn to move into the bunker?"

Dean blinked, and turned around with a perplexed frown. Wait, what? Realization finally hit, and he could have kicked himself. "You mean you and Ryn are gonna go back to her place to bring some of her stuff back to the bunker?" he clarified.

Cas's brows knitted together. "Yes. What did you think I meant?"

Dean shook his head, feeling like an idiot. "Nothin'. The car runs fine now. The rest of the repairs are mostly cosmetic anyway. They can wait until you get back."

Cas gazed at him uncertainly for a moment longer before relaxing. "Thank you."

"No problem." Sheesh, of course Ryn wanted to get some of her stuff. She was probably tired of borrowing clothes any time she happened to burst into a flaming bird.

Cas gave him another one of those hesitant smiles. "Ryn used to translate ancient texts for monks in medieval England," he said. "She could become a Woman of Letters here."

Dean had to take a moment to follow that jump in the conversation. Seriously, if Cas drove the way he switched mental gears, that Continental was gonna need a ton of maintenance. "Okay, cool." They had a bunch of lore in languages they couldn't read, though usually they just asked Cas for help with that.

Dean paused, eyeing the angel intently and noting the way he was shifting his weight almost nervously. Dean could have sighed. "You know that neither Ryn or you have to earn your keep or anything, right? This is your home as much as it is me and Sam's."

Cas fidgeted. "Yes, I know. I just…" He huffed out what seemed to be frustration. "It's good to have a purpose."

Dean nodded in understanding. Their whole lives had been about the mission, whether it was hunting the demon that killed their mom, or stopping the Apocalypse, or saving the other from their latest boneheaded mistake. Even now, with things settling down and being okay, Dean knew he and Sam would get back to hunting. That was just their lives. The family business. And he figured Cas and Ryn would join them sometimes.

"Well, whether you two become full-time book worms or come on hunts with us, just know that it's been nice having you around. Both of you. I know Sam feels the same."

Cas's lips tugged upward with that shy smile again. It was getting easier to draw it out these days, which Dean was glad for.

"Thank you, Dean," Cas said sincerely.

"Yeah, yeah," he mumbled. How was he getting roped into so many chick-flick moments lately? "Go find your girlfriend."

Dean turned back to the Continental and double-checked all the wires and connections, just to make sure Cas wouldn't have any problems on the road. The angel was a quick study, but Dean didn't want them having to worry about anything.

Once he was satisfied, he rinsed his hands at the work sink and put everything away before heading inside. He found Sam in the library, watching something on his laptop that looked suspiciously like Downtown Abbey. The worst part was Dean couldn't even blame it on them having a female in the bunker.

"Dude, really?" he said, dropping into the seat across from his brother.

Sam jerked almost guiltily, and quickly closed the laptop. "Uh, hey."

"So Cas and Ryn are gonna take off for a couple days," Dean said, foregoing any snarky remarks he could have made, for the moment. "Get some things from her place to bring back here."

"Oh. Okay." Sam quirked a brow. "Like what?"

Dean snorted. "Change of clothes would be good," he muttered.

Sam's cheeks pinked slightly. "Oh, right. Yeah."

Dean smirked in amusement. Sometimes it was easy to forget that not all supernatural beings went around in the same get-up for years on end.

"So if they're gonna be busy doing that," Dean went on. "I figure we can get back to looking for cases."

Sam leaned back in his chair, cocking his head thoughtfully. "Yeah, sure. I've been starting to get a little bored."

"Obviously," Dean remarked dryly, flicking a pointed look at the laptop.

His brother scowled. "Dude, don't judge. It's a hit series."

"Whatever you say, Samantha."

"Jerk."

"Bitch."

And with that, they both reached for their respective laptops to start searching for their next hunt.

Ryn sat on the edge of the bed, wringing her hands in her lap. She didn't know what to do. Of all the ways she'd expected her life to go, this was not one of them. Not even close. She'd teamed up with a couple of hunters, bound herself to an angel, fought against a primordial evil that almost devoured the world, and now…now she didn't even know what to make of things.

She dropped her head into her hands and clutched at her hair. How had it all gotten so complicated?

The door squeaked open and Ryn jolted upright as Castiel came in. He always moved so soundlessly in the halls, she hadn't heard him approaching.

"Dean has finished fixing the car," he informed her. "So we can finally make it back to your cabin to get your things." He canted a rueful look at her. "I'm sorry for all the detours previously. I promise not to make any this time."

Ryn closed her eyes under a wave of remorse. She was the one about to throw a massive detour at him.

"Ryn, what's wrong?"

She couldn't bear the concern in his voice, and was afraid to open her eyes and see it on his face.

"I'm pregnant."

Silence greeted her announcement, and she finally forced herself to look. Castiel was staring at her blankly.

"Cas?"

His expression remained completely uncomprehending. "I don't understand."

Ryn took a deep breath and let it out slowly. "I'm pregnant. With a child. With our child."

She'd known that morning that something was different, something was off. The thrum she'd been feeling for the past few days, she'd attributed to simply being happy and content. But that thrum had blossomed into a distinct note, one completely different from the chord of her own inner fire. It had similarities…but also a flute-like lilt as rich and ethereal as the angel's grace she would instantly recognize among a cacophony of other auroras.

And that's when she'd known beyond a shadow of doubt what was somehow growing inside her.

Ryn watched the lines of Castiel's face furrow as he continued to parse her words out, and then as they slackened in shock. "N-no. No, that's impossible."

She let out a humorless snort. "Believe me, I'm just as shocked."

Castiel's expression began to shift through a myriad of emotions that Ryn couldn't hope to keep up with. He pivoted on his heel one direction, then the other, as though he couldn't decide where to go.

"Alright," he said firmly. "How do we get rid of it?"

Ryn's brows rose in dismay. "Get rid of it?"

"Yes. Is there…surely there must be something. Something in the Men of Letters archives." He turned toward the door.

"I'm not getting rid of it," she called after him, flabbergasted that he would even jump to that.

He whirled back around. "You- you can't think of keeping it. It's an abomination!"

Her heart clenched at the derogatory term and growing look of horror on his face. "It is not."

Castiel's eyes widened further. "Is it influencing you? That's what it's doing, isn't it? A survival mechanism, enslaving the mother." He turned and swept out of the room.

"Cas, wait!" Ryn hurried after him, barreling into the library on the coattails of his crackling storm. Sam and Dean were sitting at two study tables with their computers, but had looked up in surprise and confusion at their explosive entrance.

"Uh, what's going on?" Sam asked hesitantly, twisting sideways in his seat to look at them.

Castiel pulled up short, ignoring the question and jerking his gaze around the bookshelves as though he wasn't sure where to start.

Ryn's throat tightened; she really didn't want to have this out in front of everyone. But the Winchesters were glancing between her and Cas in concern and some nervousness, and there was no putting this cat back in the bag.

"I'm pregnant," she ground out for the third time. As if not saying it out loud could make it any less real than it already was.

The brothers had much the same reaction as Castiel: brows shooting upward and mouths moving soundlessly.

"I'm sorry, what?" Dean stammered, before indignation quickly overtook his stupefaction. "With whose baby?"

Ryn shot him a scathing look and gestured sharply at Castiel.

And then Dean was looking flummoxed again. "Wait, you and Cas…? You two actually…?"

"That is how babies are conceived," Castiel spat, tone laced with venom.

Ryn folded her arms across her stomach defensively. She'd known he would likely be upset. They hadn't planned this, hadn't even discussed it. But she hadn't expected such…vitriol.

Dean sputtered in disbelief. "Didn't you use protection?"

"Yes," Castiel growled at the hunter, then turned back to Ryn, his expression suddenly wrecked with devastation. "I don't understand how this happened."

Sam and Dean turned questioning looks on her as well, and Ryn winced under their borderline judgmental gazes. It wasn't like it was her fault. "Those things aren't always one-hundred percent foolproof," she pointed out. "Look, Cas, I'm sorry. I didn't ask for this. But it's what's happened."

Castiel shook his head and turned away. "We never should have…I should have known better. What we did…it's a horrible sin." He looked back at them all. "The spawn needs to be terminated."

Ryn stiffened again. "I'm not killing our baby!"

"Whoa, whoa," Dean jumped in, both him and Sam rising from their seats. "Let's back up a second."

"Nephilim are forbidden by the oldest laws in Heaven," Castiel insisted. "They grow into their power and then…" He ground his teeth in clear frustration.

"And then what?" Sam asked.

"Entire worlds die."

Ryn hugged herself tighter. She didn't care about Heaven's laws. Heaven was a cold, cruel place full of calculating torture and oppression. According to Heaven, she herself was just another abomination. According to them, Castiel was an aberration, an angel to be scorned, when the truth was he was the most selfless and devout one of them all.

"Um, okay," Sam said tentatively, eyeing Castiel's still tense posture. "But a nephilim is a child of an angel and a human, and Ryn isn't human."

"No, she's the Alpha phoenix, which means this thing will grow up to be something even more powerful, even more deadly!"

"Cas, calm down," Dean interjected.

Castiel whirled on him. "I will not calm down! Don't you understand what I've done? This doesn't even come close to all the atrocities I've committed in the past. I've broken one of Heaven's most sacred commands, created an abomination—"

"Stop calling it that!" Ryn exploded, silencing the room.

All three of them startled, and Sam and Dean gave her contrite looks, while Castiel's mouth pressed into a tight line.

Ryn gave him a pleading look. "Cas, please."

His blue irises were roiling tempests as he gazed back at her. And then he wrenched away and stormed out of the library. She heard his echoing footsteps clomp up the stairs, and the grating sound of the front door followed a moment later. She flinched as it slammed shut, the reverberations of anger resounding through the bunker.

The awkward tension in the room was palpable, and Ryn glanced at Sam and Dean, who were exchanging unreadable looks with each other. She suddenly wanted to be anywhere else.

Dean cleared his throat. "Just, uh, give him some time to cool off."

"I'm sorry," she said hoarsely. "I didn't mean to ruin things."

And why did it have to ruin everything? This should have been something happy. A miracle. Not a curse. It had been so long since she'd had a child… Despite what had happened to Edan, Ryn had loved him. And she hadn't thought she'd get such a chance again.

"So, this baby," Sam spoke up. "It's essentially half phoenix, half angel? What does that mean?"

She shrugged one shoulder helplessly. "I don't know. It's not like this has ever happened before."

Dean let out a small snort. "Yeah, you guys are pretty much trying to break the mold in everything, huh?" He ran a hand over his hair. "Okay, so, what's the timeline we're looking at here? Nine months?"

"I don't know."

"Is this thing gonna spontaneous burst into flames after it's born? Before it's born?"

"I don't know."

"Do you know anything?" Dean asked sharply, but then gave himself a rough shake and flashed her a look of apology. "Sorry, I just…we need to know if this thing is a threat like Cas says."

Hot moisture burned at the corners of her eyes, and she settled her hands over her stomach, listening to the steady thrum within. "I don't have answers for you," she said weakly. "Except that you don't feel what I do. This spark, this brand new spark inside me…it doesn't feel evil." Her voice dropped to a whisper. "Doesn't feel like a monster."

Sam and Dean exchanged another look, and Ryn closed her eyes against a swell of tears, feeling utterly alone.

A/N: Yup, I went there. Honestly, when this idea first came to me, I was very leery. But then I was tickled by the image of a proud Uncle Dean…and things spiraled from there. So I know it's a rough start, but things will get better!