They were watching Game of Thrones and Dean was drooling over the dragons when Castiel appeared at the door, his eyes immediately locked on Dean.
"Hey Cas, what's the word?" Dean asked, actually in a good mood after watching "that dick Joffrey" die a brutal death.
"Sam, you should probably exit the room now." Castiel's eyes left Dean for all of half a second to acknowledge Sam's presence. Cas was already striding toward the bed, loosening his tie and dropping his trench coat to the ground in swift, deliberate motions.
Sam lept up from the comfy chair as Cas crawled onto the bed with Dean without hesitation.
"Oh, son of a-" Dean muttered, scrambling up against the headboard. "What are you doing?" He protested, his eyes on Sam and his cheeks flaring bright red.
"We are, in explicit terms, very safe from repeated accidental conception. I checked." Castiel explained, throwing a leg over Dean's hips and leaning to press eager kisses on Dean's surprised mouth.
Sam was almost running for the door at that point.
"Cas, will you just hold the fuck up for two second?" was the last thing Sam heard Dean laugh as he bolted through the door and shut it hard behind him.
They were not quiet. In fact, Sam was fairly certain it was the loudest sex he's ever been in the vicinity of, including his own sexual experiences.
Sam checked in on Dean about once a day after that, tentatively knocking at the door and waiting for Cas to magic the room back in order, or magic them clothes or something because half the time it's wrecked and the other half the time it's spotless, but Dean always has this happy, sated look on his face when Sam cautiously peaks in through the door to check he's still alive. Cas must have used his funky angel magic to soundproof the room after that, thank god, because Sam was sure they didn't actually get quieter.
Dean didn't look any different physically, but Cas would stare at him from time to time and nod his head approvingly.
"She is growing well." He said one day after squinting at Dean for several minutes. Apparently, as little as Sam liked to think about it, Dean was less exhausted with Cas... contributing... to the growth of the nephilim. Enough that he had the energy to come downstairs for breakfast, anyway.
Dean looked unsettled but he didn't say anything. He poured himself more orange juice.
"Can you feel it? Uh, I mean her?" Sam asked, correcting himself after Cas' face fell in disappointment. They still routinely called her an 'it', but Cas hated that.
"She's just an invisible energy mosquito right now, Cas. Sorry, It's hard to wrap our heads around. Human babies are much more..." Dean searched for the word and Sam helped him out with, "tangible?"
"Yeah, yeah. We can see and feel them. I can't even, uh, 'sense' her as you call it. I'm just pooped 24/7, that's all I know."
"You can, though. You said you had strong maternal feelings for her." Cas argued, clearly upset. He crossed his arms.
"Uh, paternal. Paternal feelings. I'm no mommy." Dean corrected him immediately. "You are not teaching her to call me mommy!" He glared at Cas, pointing sternly.
"Of course." Sam could have sworn he saw a shit-eating grin flicker over Cas' mouth. "Of course you're a father as well, Dean."
Dean rolled his eyes and shoved more bacon in his mouth.
It took about four months. Cas slept in Dean's room- well, "slept"- and Dean had to admit, his exhaustion was far less when Cas was around, even if he was just sleeping peacefully, curled up against Dean's back.
Cas liked to stare at him even more than usual, and the usual amount was a lot. Dean had no choice but to get used to it. Cas would squint intensely at him, but not really at him, as though he were trying to see through Dean, which admittedly was probably exactly what he was doing. Dean would read or do laundry or listen to music as Cas sat and stared for minutes at a time, completely unmoving, just an intense statue of fatherly intent.
Dean started to think more of it as a 'her'; not as much because of the happy gushy feeling in his chest, but more from the way Cas would talk about her. Dean started to wish he could see her like Cas could see her, even if she was just white and blue sparks of energy as Cas described. Cas was enthralled with Dean and with the child, and Dean woke up more than once to Cas mumbling praise to them both as he pressed gentle kisses to the top of Dean's head.
Still, he was simultaneously terrified and relieved when one day Cas announced as they picked out Q-tips and shampoo in the grocery store,
"It's almost time, Dean. We should get you back to the bunker immediately."
Dean gaped at Cas' sudden shift to mega intense, FBI body gaurding the president sort of attitude as he stepped closer to Dean and once over'd the grocery store as though scanning for people he should murder.
"What? Now?" Dean asked, and he was glad Sam was off in the dairy department searching for his hippie yogurt so he didn't hear the fearful squeak in Dean's voice.
"Yes. Now. Sam can meet us, but I must take you right at this moment before it becomes dangerous for everyone here."
He touched Dean's shoulder and suddenly they were in Dean's room.
"Give a guy a chance to text his brother." Dean grumbled as he whipped out his phone.
A blinding pain suddenly whited out his whole world. He was certain someone was trying to tear his body in two, and the agony was almost too much to bear.
Then, like a wave receding, it dimmed enough that Dean could register that he was on the bed, Cas was next to him propping his head up on pillows, and he was sweating through his jacket.
"Hot." Dean managed. The next second it was gone, everything but his boxers, and Cas' piercing blue eyes hovered, concerned, in his swimming vision.
"Is that better?" His low gravelly was soothing against the ebbing sensation of agony threatening to return.
"Fuck, Cas. I really got the bum end of this deal." Dean muttered, grabbing for Cas' hand as another wave of pain swept through him.
"It will not last long, Dean." Cas reassured him. Dean appreciated Cas' voice frequently, if silently, but contrasted to the sensation of nails being pounded into his spine and head it was especially wonderful to hear.
"It better no- aaaAAAHH!" Dean broke off into a yell as another wave of nausea and the inexplicable tearing feeling ripped through him again.
Castiel was muttering to himself in Enochian when Dean next came to, his eyes glowing white as looming, jet black wings seemed to materialize out of the hot air of the room, cocooning around Dean protectively. Dean would never admit to clutching at Cas' for support, but shit. It hurt like a bitch.
Whatever Cas was doing, it helped. Dean could breathe again.
"I should have taken those damn lamaze classes." Dean managed, earning nothing but a look of pure confusion from Cas before he decided to ignore him and return to his Enochian chanting.
Dean didn't know how long it lasted, bearing the waves of tearing and shifting and other bizarre feelings he didn't even know he could have before that. They weren't entirely bodily, though his body reacted as though he were being tortured; he was sweating profusely, shaking, and he couldn't have gotten to his feet even if he tried.
Then, as suddenly as it started, it stopped.
Cas' eyes went wide as Dean panted, shaking on the bed, and looked around in confusion.
"Oh. Oh, it's beautiful, Dean." Cas whispered, tears in his eyes and awe in his gaze as he stared straight through Dean.
The agony him him as though he were falling through the air and didn't even realize until he crashed into a hard sheet of water and was enveloped in a sheet of icy acid.
Dean screamed.
He didn't open his eyes until Cas' rough hands, petting at him nervously, brought him back out of his head. The pain was gone, though he didn't trust that anymore, not after that last... contraction? Was that what the fuck those were?
"Dean, wake up. Dean. You're alright. She's here."
Dean blinked and looked around blearily as Cas lifted his upper body into his arms so Dean had a better view of the room.
Her hair was long and wavy, darker than Dean's but not by much. Her eyes were summer under the hot sun. She looked around the room as though cataloguing everything she saw into a list in her mind; he could almost see her thinking "these are the things of humans".
"Fathers." Her voice was lilting and sweet, and it sounded nothing like either one of them.
Dean loved her.
He couldn't explain it, but he loved her immediately.
She called him 'father', so thankfully he didn't need to think about that one too hard, especially after what he could only describe as debilitating contractions.
She approached them. She was fully clothed, somehow, in dress clothes, like the other angels. She looked about 18, which Dean also tried not to think too hard about. Angel magic, apparently, included dressing and aging children, which he was 100% onboard with considering he got to skip all the diaper changing. She climbed onto the bed with them snuggled into both of their embraces, and to Dean's mortification ,tears clouded his eyes as he realized she smelled like his mother used to.
Mary. Yes, that was a good name for her.
Oh god, how he loved her.
He didn't want to let go, and she seemed perfectly content to breathe in the scent of Cas' shoulder and laugh at how they cried over her, feeling Dean's hair curiously and running a hand along his cheek as though discovering what it was to touch another person.
Castiel had explained to Dean that she would have a lot of instinctual knowledge about life from sharing a soul with Dean for months, so Dean was curious to find out what she knew and what she didn't. He imagined it would be a lot like the first time he met Cas, his baby in a trenchcoat, and reteaching him all over again in their daughter.
Eventually Sam made it back, his hair wild and windswept as he took in the scene in the bedroom, his eyes panicked. Mary called him uncle and ran to hug him too. Dean felt empty when she left his side, even just to cross to the other side of the room, and he knew he was totally gone on her.
Cas was grinning, wiping a stray tear from his eyes before he kissed Dean's cheek.
"I want to apologize to you for accidentally impregnating you, but I can't manage to feel sorry about it. I haven't been able to since the moment I realized." Cas whispered so just Dean could hear. Sam was crying too, that sap, and Mary was laughing joyously and wiping at his tears. She lifted a wet finger to her tongue and tilted her head curiously. Sam watched her in surprise and then started laughing.
"I'm not sorry, either." Dean smiled, watching Sam pull Mary into a hug again.