A/N- So the summary is pretty much the best description of this work without giving too much away. (Shh... spoliers!) ;) Also, I made a mini playlist you can listen to while you read this if you want; though you'll probaly finish reading it before the music ends. It's just some songs that inspired the one-shot, and that I listened to as I wrote it.

"Magic Number Twelve" Playlist
1) Life and Death by Paul Cardall
2) Kiss Me by Ed Sheeran
3) Close Your Eyes by Michael Buble

Also, please excuse typos and careless error. I did edit over this, but I'm horrible at catching my own mistakes. If you like it, please drop a comment or a kudos? Castiel will smile down on you elegantly. Me, I'll cry in a ball on my floor from gratefulness. (Who? Me? Over-exaggerate? No.) Anyways, thanks for taking the time to read this, hope you enjoy it! :)

Dean couldn't go back.
Back to Lisa, that is.
He had driven to there house, and parked outside of it in the street for a few moments. The TV was blaring. Soft golden light spilled out, nearly reaching Dean's car. He could see the satin sheen of the cliched wooden dinner table. Lisa was in the kitchen preparing dinner, her mouth opened in what was distinctively a laugh in response to the phone she clutched against her ear.
As the engine idled quietly, Dean felt like he was much farther away than just a street. He wasn't sure if he could still laugh like.
Actually, he was pretty sure he couldn't.
Dean blew out a deep sigh and gave a soft laugh of a different sort.
"I'm sorry Sammy." He muttered, voice hitching a bit on his brother's name.
He shifted into drive, and the car gave it's distinctive purr as it drove away into the darkness, and away from what might have been.
Inside the house, Lisa peered out the window, thinking she might have heard a familiar sound.
_

Dean gripped the steering wheel tight.
The white-knuckled hold was nothing new for him. He had held the wheel a bit too tight before; when Sammy tried to argue with him, when he was racing down the street on a particularly dark night. Or more recently, when he was driving into a battle had less and less hope of winning.
Dean grip on the wheel loosened. But they had won, right?
So why was the seat next to him empty?
Dean reached over to jam a tape into the player. He fumbled with it for a moment, not looking at what it was. His body wouldn't seem to do what he asked, and the tape slipped out of his fingers, falling under the passenger seat. Dean cursed under his breath.
Sam would use be the one to help him put music in.
Dean slammed on the brakes, and jerked the car over to the side of the road. He hardly heard the blare of the horn as the car behind him sped into the darkness.
Dean rested his forehead of the cool hardness of the steering wheel.
This is what they had wanted; what they had worked so hard for. Sam got to save the world, and Dean was supposed to live a normal life. Yet the thoughts in Dean's head weren't normal. They were thoughts of crossroad deals and where he might be able to find a summoning ritual for Death.
Thoughts of how to bring his baby brother back.
Because Dean couldn't handle this. The vast emptiness. The loneliness.
He slammed his hand against the dash, fighting the moisture welling up in his eyes with every ounce of his being.
Twelve. He just had to hold out for twelve.
Dean squeezed his eyes shut once before opening them again to put the Impala into drive, and sped away.
_

The motel lady dropped the keys into the counter with the same type of carelessness every worker who had this position did. It was the clunk of here-take'em-I-don't-care-what-you-do-just-don't-b urn-the-room-down. Same clinking of keys on the counter, same unspoken dialogue as always. If you knew the drill at these sort of places like Dean did, you showed your experience by not asking any questions. He did even bother faking a smile at the lady as he slid the keys across the counter. Besides, she seemed to be more interested in some trashy tabloid then caring about Dean and his a "pleasant stay".
Alone in his room, Dean sat at the edge of the bed, staring off into space. He figured he'd look catatonic to anyone who walked in. Which was appropriate, because that how he felt. Frozen, empty, and too numb to feel much.
Dean glanced at the red stick numbers displayed on the crappy hotel analog clock. 11:46 PM. Which meant only a handful of minutes left until midnight. Dean scrubbed his face in frustration. He wished he could jut cry like a normal person. But he knew if he started crying in that way, he'd never stop. And he couldn't afford the luxury of actually going catatonic. No, Dean Winchester had people who depended on him. He was to be saving people, hunting, the whole family business line of crap.
He snorted. That's how this whole thing had started. When Dean was young, about the age of nine, his father would often be out late on hunts. It would just be him and Sam. And Dean would be alone with his thoughts and memories from all the hunts he had already been on. They were terrifying; visions of shredded bodies and sharp things dripping with blood would play in his memories. He wanted so badly to let the tears fall. But his Dad had made him promise he would be strong for Sammy. Because he couldn't let his brother see that contagious fear. Still, Dean wasn't that strong. Finally he decided there was a time he could cry.
And that was 12:00 AM to 1:00 AM. Because that was the midnight hour. If midnight was the meant the change to the next day, but midnight was still the last part of the previous day, where did that whole hour fall? Was it part of that day or the next. It was like... it didn't really exist. A time when time didn't exist, and he could cry without consequences. So in Dean's stupid child logic, he would cry in that allotted slot of time, because those tears wouldn't exactly be real.
Now that he was older, Dean knew how stupid and pointless, even a bit girly, his childhood tradition was. But this was his way of coping. Crying in his little nonexistent period was the only way Dean could let out what he felt without it haunting him.
Dean looked at the clock again. 11:53 PM. Twelve o'clock couldn't come quickly enough.
Dean buried his face in his hands and drew a deep breathe, trying to barricade himself against the pain for just a few more minutes.
"Hello Dean."
Dean jerked his head out of his hands.
"Cas? What are you doing here? How did you find me?" Dean asked, clearing his throat so his voice wouldn't crack. Panic began to rise in him. He needed Cas to leave. It was nearly midnight.
"I just..." The angel gestured vaguely. "Wanted to make certain you were okay." Castiel finished.
Dean gave him a heavy look of disbelief. "Really Cas? What do you expect? For me to throw a party? Well," Dean said with a tight smile as he held up a beer. "This is as close as I'm going to get. We may have saved the whole world Cas, but we couldn't save most of mine." Dean said, voice slipping of in pain at the end of the sentence. He shouldn't be venting all his chick flick feelings to Cas.
The look Cas gave Dean made him automatically defensive. It was a look of concern, and compassion.
"Dean, I was only asking about your physical state. I may not know as much as some about human culture, but I know better than to assume that." Cas said slowly, watching Dean as if he might erupt at any moment.
Dean turned his head away, chugging another swallow of his beer before placing it on the bedside table to the the alarm clock.
11:58 PM.
"Cas, I get it, and I'm fine. Shouldn't you be upstairs consulting with the other big-wings in Heaven right about now? Ya know, making sure no one started a holy oil fire?" Dean said, ready for Cas to leave.
Cas narrowed his eyes with curiosity. 'I've been there already. I will admit the shape that it is in is not... ideal. But I found your concerns much pressing."
"I'm fine. Don't worry about it." Dean said in the most monotone voice he could muster.
"I distinctly remember you just saying something about not being fine. You can't fool me Dean. I know your pain." Castiel's voice softened at the end.
Dean fought an irrational tide of anger.
"What do you know about my pain? Huh Cas?! Tell me how you could possibly understand an emptiness in your heart. And knowing it's gonna be there forever because you don't just 'get over' watching your brother die." Dean didn't even realized he was clawing the covers until he stopped speaking.
"You forget how many of my own brothers I murdered in order to help achieve this outcome. This outcome that you and your brother asked for. Do not make the mistake of thinking this cost me nothing. Sam may not have been my brother, but he was my friend as well." Castiel said, just a hint of steel in his light blue eyes. His back was rigid, unbroken.
The only thing worse than pain is being reminded of someone's pain. Someone else who shared your pain, and had some hint of what it was like. Somehow that seemed worse than drowning in the darkness alone. It wasn't as if he felt he was the only one allowed to be in pain. No, it was more like floating downward in a cold ocean, and watching the sun disappear. And before you closed your eyes, because you knew your were going to die, you looked to your left and saw someone else you cared about drowning too. Someone with eye brighter than any ocean.
Dean looked away from Cas to the clock.
12:02 AM.
Dean couldn't hold his breath any more. He had to breathe, or later the water would fill this lungs and he would never climb off the ocean floor.
"I'm sorry Castiel." Dean said, sorry in so many different ways. Sorry he had insulted him. Sorry he had broken the one life he had ever known. Sorry he had hurt someone else he cared about. Sorry because Sam was gone. Sorry because right then Dean started to cry, in front of the angel.
It was just one small tear at first. One perfect tear that was a special, unselfish tear for his brother. It looked like a tiny crystal, glowing white from the dim light streaming in from the window as it fell. It hit the dusty expanse between Dean and Cas, not making a sound but moving mountains between them. The sob that choked out next was for the pain that didn't leave with Sammy. He buried his face in his hands. How could he be so weak?
"Dean."
Dean hadn't heard his name said like that in a long time. For just a moment, the face of his mother flashed in his mind.
"I'm-" But before Dean could finish, he felt a weight dip the side of the bed next to him and a warmth envelope his shoulders. It was Cas, embracing him like he had forgotten that cruel words Dean had said only moments before.
"It's okay, Dean." Cas said, voice soothing in the way only the angel's gravely voice could be. How could he say it was okay? He knew Dean well enough to know what a loss cause he was without his baby brother. Protecting Sam was his one purpose in life for so long, the only thing that kept things even close to okay.
"What I mean is, it's okay to cry." Cas said, softly as if he was afraid to break Dean. As if Dean, part of he team that took down the apocalypse, was so easily snapped in half.
Well, actually he did feel pretty damn breakable right about now.
At that thought Dean turned and smothered his face into Castiel's shirt. Dean cried like he never had before. The entire time, Castiel just held him, eventually pulling him completely on the bed. Every tear was pain; pain for ever single freak'en thing that had happened since that house fire when he was young, and every single thing that would happen. He cried because he had to get rid of it; he couldn't carry around all the hurt and darkness anymore. Dean didn't know long he sat there with sobs erupting from him, and he didn't try to keep track of time. Time wasn't important anymore. It ceased to matter. He would weep some till everything was gone, and in Dean's life that was a lot to get rid of. Finally Dean began to realize that he had cried everything, yet there was something very tangible and warm still there. Bit by bit coherence began to return to him as the tears lessened.
The first thing he noticed was the smell of Cas. It consumed his senses with the fresh smell of vanilla and spice, and maybe even a bit a lavender from fabric softener. Dean realized he should probably be really embarrassed and defending his manhood right now, but a passing thought was all he gave that notion. The second thing Dean noticed was the way Castiel was slowly rubbing Dean's back, softly muttering things to him.
"-and then the humans began to learn how to heal things. Which was extraordinary to us, because after seeing the simple human destroy so many things, it was a wondrous miracle to see them repair." Cas said, undaunted by Dean slow shift into alertness.
"Cas? What are you doing?" Dean asked, voice still wrecked from the countless tears.
"Hmm? Oh, I'm telling you the story of creation and humanity. It's a very good one, even though it's a bit sad a times. But astonishingly, even when things are at there worst, humans never seems to lose their hearts. Not completely." Cas said, giving Dean a meaningful look as he spoke.
Dean sat up a little, still nestled in Castiel. "Are you trying to say something about me?" he said, cocking his eyebrow in the smallest bit of humor and sarcasm.
Castiel, however, was deadly serious. He place his hands on either side of Dean's face. His eyes glowed like heaven as they drank in Dean's face. Dean could almost feel their light on him. Castiel had never looked at him like his, like he was so cherished. Or maybe Dean was wrong, and Cas had looked at him like this before, but it was Dean that wasn't truly seeing.
"No, Dean. Because as much as you've hidden it from the world that tries to hurt you, you've never once lost any part of your heart." Castiel said each words carefully, and as full of emotion as Dean had ever heard in the angel's voice.
Dean choked a bit, and his gaze fell down, while is face remained in Cas' hands.
"How can you say that Cas, when you've seen everything I've done. And just half of the things I done that have hurt you-" Guilt hit Dean like the heaviest burden as he spoke. He was empty of tears, but not of memories.
"I'm sorry, but this time you are wrong."
Dean looked back up into Castiel's ageless face, intent expression holding Dean in place. "Actions only carry so much weight. I have seen more than just the things you've done. I have seen your soul, Dean Winchester." With those words, Castiel's hand slid down his face, then neck, not stopping until it was underneath this sleeve and lined up precisely with the hand print there.
A line of fire and ice crawled up Dean's arm at the touch. And as the angel's hand lay there, something concrete shifted inside him. It didn't really like he was being rearranged, or changed. But it was as if that very heart Castiel had just spoke of had swollen, and now he saw the piece of it that was meant for someone else.
Someone else who had always stood by him, who had given up everything he had for him. Left all of it -family, friends, everything he knew and valued- behind for the hunter with a shielded heart and broken eyes. And Dean was staring into that person's eyes, and for the first time truly looking at the miracle that had landed in front of him; the one he didn't believe could happen. Someone besides his brother who had did the impossible, and loved him. Loved in a way Dean had just given up looking for.
He loved him. Loved him.
Another person loved him.
That person's name was Castiel.
Without a word, because words weren't needed, Cas lowered his head towards Dean. Dean's lips caught him halfway. The kiss was soft and simple, yet long and full of love. It felt like coming home and starting fresh all at once. Cas' lips were impossibly chapped and yet smooth, with only the pure taste of Castiel's spice. It was an amazing sensation, kissing and not looking for more. It was like he had been pulled out of the stormy ocean and was now in a safe harbor. Dean had never felt so safe-had never trusted anyone besides Sammy to keep him safe. The world took on a soft glow as Dean fought to keep him eyes open.
Castiel pulled away, and for a moment the drowsy Dean tried to follow his lips.
"Close your eyes, Dean. You can rest now." Cas said gently stroking Dean's hair. And maybe Dean actually could. Maybe it was Dean's turn for a rest, for a bit of a break.
He let his eyes fall shut, and the world turned the warmest black.
Dean drifted on the edge of sleep, aware that Castiel had began methodically reciting his story of the human race again. But completely unaware that the clock now read 2:07 AM, and that he had only stopped crying about thirty minutes ago. Dean did know how vulnerable that moment had been, and he wasn't sure if he could ever be that open again. But he was certain something had changed for the better, and he was going to clinging to that rope and not let go.
Humans hardly ever remember the second before they drift off to sleep. So it is uncertainly if Dean would remember it the next day, or any time after that; but in that one moment Dean could have sworn he heard Castiel's soft storytelling voice say: "-and then Mary Winchester leaned down to her son and spoke to him the most important words in the universe-"
Angels are watching over you.