Cas had shown up in Dean's room in the bunker, just as he was about to go to sleep. Before Dean could tell him he needed his four hours, he told him he was leaving.
"What? Where are you going? For how long?" Dean crossed the room to stand in front of Cas, who sighed and looked away.
"Indefinitely, I'm assuming."
Cas wasn't looking at him now, focusing his eyes on the floor instead.
Dean wasn't sure how to respond, how could he leave them when they needed him most? With Sam going through the trials, and Crowley constantly on their ass.
So he settled for a simple question. "Why?"
Cas continued staring at the floor, his hands twiddling with the side of that goddamn trench coat.
"Metatron and I are... Closing off Heaven, locking all the angels away."
"So you get locked away too."
Dean meant it as a question, but it came out sounding more like a statement.
Cas nodded solemnly.
"But why are you doing this?" Dean stepped forward, invading Cas' personal space.
"It will be better, for the humans. The angels will not be able to bring their problems onto Earth. I'm doing it to protect humans," Cas looked up, staring at the wall where Dean had all his guns on display, "to protect you." He muttered, looking back down. Dean let out a sigh, rubbing his hand over his face.
"So when do you leave?"
Finally Cas looked up from staring at the floor, looking Dean in the eyes before he continued speaking. "Tonight. We have one more trial to complete. I've already said goodbye to Sam, after this I'm completing the last one and.." Cas was unable to finish his sentence, looking down at the floor again.
Dean awkwardly rubbed a hand over the back of his neck. "So this is it?"
Cas nodded, and that's when Dean stepped forward and pulled him into a hug, resting his chin on the top of Cas' eternally messy hair. Cas just stood there at first, before wrapping his arms around Dean's waist and burying his head in the crook of Dean's neck.
"I'm gonna miss you, you stupid son of a bitch."
Cas let out a sad chuckle, pulling away from Dean. He stood there, just staring at Dean. There was a palpable silence, before Dean broke it, "Before you go uh..." He paused, unsure how to put all the things he felt about Cas into words. Cas tilted his head to the side, squinting his eyes. The action almost broke Dean's heart, upon the realization he would never see it again.
"You know what, screw it."
Dean leaned forward and placed a chaste kiss on Cas' lips, knowing if he did anything more he wouldn't be able to stop himself.
Cas looked up, surprise covering his face.
"I need you," Dean gripped Cas' shoulders, staring into his eyes, "don't ever forget that."
Cas smiled sadly and Dean could have sworn he saw tears in those stunning blue eyes.
"Goodbye, Dean."
There was the rustling of wings that had become so familiar, and Cas was gone. For good this time.
The next morning Dean wandered into the kitchen, deciding that it was never too early for alcohol. He began looking through the fridge for beer when he decided this was more of a whisky problem.
Sam came in to find Dean slumped in a chair at the table, on his second glass. Sam stared at Dean, as if he was debating whether or not to confiscate the alcohol, he eventually just sat down across from Dean, looking at him for a little longer before breaking the silence.
"So, I'm guessing you talked to Cas last night?"
Dean let out a grunt in answer, taking another sip of whisky.
"Do you wanna talk about it?"
Dean stood up, grabbing the whisky bottle and glass. "Nothing to talk about Sammy." With that he disappeared into his room.
At 4:23, Dean found Sam sitting in the library, flipping through an ancient looking book.
"Hey, I found a case nearby, a girl died from gun shot wounds but there were no guns in the house and no signs of break-ins."
Sam looked up from his book, raising an eyebrow. "Are you sure you wanna get back on the road so soon?"
"Look, I'm not some teenage girl who's gonna sit and cry because her friend left her."
"I know," Sam closed the book, paying full attention to Dean now. "But that doesn't mean you can't be sad about it."
"Okay, whatever let's just go."
Dean stalked off, heading back to his room to pack a duffle and get on the road.
The hunt went smoothly, a simple salt and burn. Weeks passed and things died down, Sam stopped bringing up Cas, and Dean had stopped moping around. But that's when the dreams started.
The first one was short, Dean was sitting on a dock, fishing, much like the one when Castiel had first popped up in his dreams. He had heard a noise behind him, and that's when he turned around to find Cas standing there. All he was able to say was a cut off shout of Dean's name, before he disappeared and Dean awoke in a cold sweat.
In the one after that, Dean had been in purgatory again. A vampire had it pushed against a tree, Dean was sure he was about to die-or whatever it is that happens in purgatory-when Cas came and chopped off it's head. But it wasn't the Cas from purgatory, with the dirtied trench coat and the mental hospital scrubs. No, this was normal, clean, backwards tie wearing Cas.
That's when Dean realized it was a dream.
Dean stared at Cas, waiting for him to break the silence. Cas looked around at the scenery, taking in the dark, gloominess of Purgatory.
"Do you dream of this often?" Cas asked, finally breaking the silence.
"Yeah, it's either this or Hell most of the time." Dean let out a dry chuckle.
Cas sighed, "I've been trying to reach you since I left."
"Cas-" Dean took a step forward, his voice breaking, but before he could say anything else, Cas' eyes grew wide, "I have to go." Then he was gone. Again.
The next one happened a few days later, Dean had been thinking about the last dream, wondering if he would ever get to see Cas. This time, he found himself standing in a generic motel room. Cas showed up next to him, looking tired.
"Hello, Dean." Cas offered a small smile, making his sad eyes brighten a little.
"Dude, how'd you get here?" Dean then looked around, "This is a dream, isn't it?"
Cas nodded, "It is the only way I am able to contact you." Cas looked around the dirtied motel room, then back at Dean. "I've missed you."
Dean's lips quirked in a small smile, turning his head to the side while nodding and shoving his hands in the pockets of his jackets.
"Yeah, back at ya man." He looked at Cas, studying his facial expression, trying to decipher something, anything. "So, how long are you here for this time?"
"Not long, I'm afraid, and I am unsure if I will be able to return...to your dreams, that is."
Dean nodded, wishing there was some way he could get Cas to stay with him. Get things back to how they used to be.
Cas stepped a little closer to Dean, staring at him with a look Dean couldn't quite place. Before alarm took over his face, Dean assumed he was hearing something over that angel radio. "I have to go soon. But Dean, that time when...when you said you needed me, did you mean-"
Dean cut him off before he could get any further, "It doesn't matter what I meant."
Cas looks at him, that same sad smile he had the day he left. Except this time, there's a small glint of happiness in his eyes, "I need you too, Dean."
Dean wakes up to the sound of his alarm blaring, but he didn't know that would be the last dream he had of Cas for a long time.