Work Text:
Sam won the bet about who would propose first. After Eileen and Jody grudgingly forked over their money, they asked him how he had known.
"I know my brother." Sam replied simply.
Sam did. Sam knew Dean better than anyone else in the world, or he had. Now someone else knew Dean as well as he did, better in some ways.
Someone else knew all of Dean's flaws and accepted him, saw the strength in him, the tenacity, and the pure humanity that shone through the cracks of his don't-give-a-fuck attitude.
Sam had been looking up to Dean since he was four, studying him, trying to be just like his big brother. Then he had been looking down at him, trying to get Dean to see him - or maybe more importantly, to get Dean to see himself. As something more than Sam's protector, as something more than daddy's blunt instrument, or at the very least, as something human.
Dean had thrown away so much of his life for Sam, including his literal life. Sam had never figured out how to pay him back for that, in fact he had just kept messing up and Dean had had to save him over and over.
Then Cas happened. Cas had challenged Dean, had learned from Dean, had finally rebelled for Dean, forsaken his entire family and millions of years of habits just for Dean.
And in doing so he had done for Dean what Sam had never been able to- show Dean that he was worth sacrifices too.
Their relationship had not been easy, starting off with a literal trip to hell and fraught with fighting - each other and also heaven and hell -, almost dying, and actually dying.
There had been a bet about when they would finally kiss, too. Sam had won that one too with, "The next time one of them dies."
The last time Cas had died; well Dean had pretty much tried his best to kill himself, turned his soul into a bomb and took off to end God's sister and himself once and for all. Then in a turn none of them saw coming, Amara had had a change of heart, thanking Dean for his service by giving him the one thing he desired more than anything.
Castiel. The angel with a crack in his chassis.
Alive and with his wings, fully angelic. Sam hadn't seen their first kiss, no one had.
Dean had tried his best to keep it a secret, Sam knew as soon as they got back to him. He had kept his mouth shut though, just for comedy's sake.
Dean finally "confessed" two weeks in, after Sam brought up the "broken washing machine" that kept thumping the wall at two in the morning.
"It's me 'n Cas." Dean had muttered under his breath.
"What?" Sam acted confused, hiding his smirk under his hair.
"It's me and Cas." Dean finally spat, glaring at Sam. "Happy? We're never talking about this again."
Sam had laughed so hard he thought he had broken a rib. Afterwards, he told Dean he had known the whole time.
Dean surprisingly didn't care about the fact the Cas was in a male vessel. He had kept it a secret just because "it's none of your goddamn business, Sammy."
Once Sam knew, it was like a whole other aspect of their relationship bloomed. Sam had never thought Dean was into PDA, at least besides making out with girls in seedy bars. Not the handholding aspect.
Turns out what Dean was into was making Cas happy, and PDA made Cas happy. Dean tried to act bothered by it, but Sam caught him pulling Cas closer, initiating the hand-holding, rubbing his nose in Cas' hair, and once, memorably, pulling Cas into his lap during movie night.
Sam teased, as a little brother should, but he was as openly supportive as Dean allowed him to be. He looked the other way when the attention was getting too much for Dean and he even gave them nights to themselves in the bunker, although that was more for his own benefit than Dean and Castiel's. They had proven time and time again they didn't care if he was in hearing range.
He also planted rainbow flags throughout the bunker, replacing them each time Dean threw them out until finally Dean left them alone.
After everything with Stiles went down, Sam worried that Dean would withdraw, retraumatized by the blatant reminder of hell and his own worst memories. Instead it seemed as if Dean and Cas had gotten closer, their profound bond becoming even deeper.
Sam watched this with a mixture of happiness and envy, and hated himself for the latter.
It had always been him that made Dean feel self-worth, taking care of him that was Dean's reason for living, and as unhealthy as it was, it was this that then made up Sam's self-worth. As long as Dean took care of him, he was worth something. He could help Dean out by having his back hunting and giving him the familiarity of their banter. He let Dean take care of him because it made Sam feel like a person. And Dean needed to take care of Sam to feel like a person.
Sam knew the textbook definition of codependency, and sometimes he thought about scratching out the definition in his copy of Miriam-Webster and just writing in his and Dean's names. Or maybe just Winchester.
Codependency breaks down when one half of the cycle no longer needs the other as much as the other needs them.
Dean didn't need Sam anymore. But Sam still needed Dean.
He kept it inside himself, knowing that Dean would deny himself happiness if he thought that's what Sam needed. Sam wouldn't be responsible for Dean breaking his own heart, not again.
Of course Dean fixed it, in his gruff no-chick-flick manner, getting Sam wasted at a bar one night after they had cleaned up a vampire nest and Cas was off checking in on Stiles.
"You know Cas ain't you, right Sammy?" Dean had grunted, barely loud enough for Sam to hear him over the din.
Sam's heart had twisted, his insecurities he thought he had hidden had been clear the whole time.
"Yeah no shit." He laughed, deflecting.
Dean had shaken his head, uncharacteristically serious. "I mean it Sammy. Cas is - Cas is something else. But he'll never be my too-big, floppy haired, pain-in-the-ass little brother, so get that through your thick skull, and then go get laid, man. Seriously."
It was typical Dean advice, and Sam had to admit that it usually worked. And somehow, weeks later, almost like fate, they ran into Eileen again on a hunt, kanima this time.
The second time around, it was the right place and the right time.
Then Sam could see Dean's relationship in a new light, it wasn't Dean moving on without him. It was Dean letting himself have what he always deserved, and now Sam could do the same.
But Dean had never been one to chase after happiness, had always been one to briefly accept the happiness that came to him and shove it away as soon as possible.
Cas was the opposite, he chased Dean down when he panicked and reminded him that Cas was not going anywhere.
Sam knew his brother.
He knew Dean had had their mother's ring resized, and that he had found a case in Depoe Bay, Oregon, that was simple enough for a two-man hunt, or so he said, so really, Sam didn't need to come, he could wine-and-dine his woman (Dean's words) and maybe "get some and finally loosen up the stick in his ass". Cas and Dean could totally handle it.
Five days later Sam was in his car, rushing to Oregon with Eileen, to rescue his brother and his brother's angel from the grip of four witches who had somehow found sigils to bind Castiel's angel power and now were going to drain them both of their life force on the full moon.
Unsurprisingly, Dean hadn't had time to propose. His next attempt failed as well, the ghost Cas and him were hunting found them first, and Cas had to spend the evening digging Dean out of the grave he had found himself in.
Sam waited for the third attempt, but it never came. Several months passed and Dean didn't try to find hunts for just him and Cas, or sneak off just him and Cas, or even take out the ring and play with it when he thought no one was watching.
Sam couldn't help it, he snooped the next time Dean made a grocery run, and found the ring in a tiny velvet pouch shoved haphazardly in the back of Dean's underwear drawer.
Sam knew his brother. He knew there were other things at play besides the simple explanation of Dean believing in fate - Dean's self-esteem mainly.
Sam took matters into his own hands, firstly leaving his laptop open to a news article about gay marriage on the bunker table while Cas was around. That didn't seem to spark anything, so he left Marriage, a History by Stephanie Cootz in the pile of books in the Dean Cave that Cas always pilfered. (Dean allowed Sam to keep his books in the Dean Cave only because Cas enjoyed them.)
He knew Cas had read it because Cas always dog-eared the pages. Still, nothing seemed to be happening. Sam was desperate. He pulled out the big guns and showed Cas Modern Family while Dean was out. Dean bitched and complained when it was all Cas wanted to watch for the next month, but he never changed the channel, or unplugged the TV like he did when Sam got turned on the History Channel.
Cas appeared pensive in the days after watching Modern Family, and commented several times on the relationship between Cam and Mitchell. Sam covertly signed up to receive ads from a couple different jewelry companies because Cas loved getting the mail, and always went through it first anyways.
Sam also made The Bet with Jody and Eileen, because he was nothing if not an opportunist.
Cas came to him in November, an ad for Blue Nile clutched in his hand.
"Sam." Cas said, characteristically serious. "I require your help. I wish to marry your brother."
So Sam finagled Cas away from Dean for a "case" in Kansas City, but really they were picking out the perfect ring, putting it all on Ronald Abernathy's card.
Then Sam fucked off for a good two weeks, citing an undercover hunt Eileen needed back-up on, and when he came back, he was two hundred dollars richer.
Dean was silent about the details and didn't even mention the engagement until Sam noticed the ring he was wearing. As hard as Sam pressed, he could not get Dean to tell him how it happened.
So he went to Cas. And it went like this:
Castiel was panicking. He had tried to cook Dean his favorite food - burgers - while Dean was in town but now the frying pan was full of black stuff, the pie was suspiciously soupy, and the whole bunker smelled awful. He spun slowly in a circle. He should have just gotten takeout, but he had really wanted to cook for Dean. Now there was no way he could get everything together before Dean came home.
He felt the ring in his pocket. Sam had been gone for a week and Castiel had done nothing but procrastinate his one job. Dean deserved something properly romantic, as the humans called it, and thus Castiel had to do this right. He had done his research on Youtube, the archive of video history. He quite liked Youtube, there was always a video explaining things Cas didn't understand, like how Dean's car worked or why humans snore.
There were even videos of proposals, thousands of them. Cas had watched them all, utilizing the incognito browser Dean had shown him so that Dean couldn't see what he had been looking at. A requirement of a proposal seemed to be the element of surprise. The other requirement was a large romantic gesture, something to show the person that you truly loved them and make them cry, although Castiel didn't understand why you would want to make someone you truly loved cry.
Nonetheless, these were the requirements. Cas didn't think Dean would like flowers, or a plane trip, or hiking to a cliff at sunset.
Cas had finally decided on a nice dinner, since that was another popular option, but it seemed like in order to be a romantic gesture it had to be cooked by the person doing the proposing specifically for the person being proposed to.
And now his big romantic gesture had gone up in flames. Castiel snapped his fingers in his frustration, the entire mess vanishing. Someone in California was going to be very confused shortly.
Cas suddenly understood the human expression of a lightbulb being turned on when an idea struck. Just in time, he heard Baby pull into the garage. Cas set off with purpose.
Dean was just pulling the groceries out of the trunk when Cas intercepted him, pulling the bags out of his hands and planting a quick kiss on his lips.
"Whoa, hey there." Dean grinned.
"Hang on to me, Dean." Cas smiled, grabbing Dean firmly by the waist.
"Whaaaaa-" Dean's question cut off as Castiel stretched his wings and flew, holding his charge tight. Unconsciously, his hand grasped Dean's right shoulder.
They landed and Dean stumbled out of Cas' grip, retching. "Jesus Cas, warn a guy- oh holy shit!"
He stumbled back into Cas' arms just as quickly, gazing around in shock.
"Did you just fly us to the top of the Eiffel Tower dude??" Dean smacked Cas' shoulder. "What the fuck Cas?"
Cas didn't reply, staring into Dean's beautiful green eyes, as he remembered the whole reason he was doing this - to show this beautiful human in front of him that Cas was never going to leave him again.
Even when Dean was long gone, from dust he came and to dust he would return, Cas would never love another.
And so Castiel, angel of the Lord, leader of garrisons, a wavelength of celestial intent, knelt to his knees in front of Dean, letting go of him with one hand to retrieve the ring from his pocket.
"Cas, what?" Dean seemed to no longer care that they were in France. His big eyes were focused only on Castiel, where they should be.
Castiel had had millions of years to formulate his vocabulary, and spoke almost every language that existed, and yet he could not find any words.
He could only hold up the ring with one hand, the other grasping the edge of Dean's coat, a parallel of a previous encounter, where Dean had saved Cas again.
The only word that would come was the word that had changed Castiel's entire world.
"Dean?"
(the tears that followed were why Dean would never tell Sam the story of Cas' proposal.)