This was a prompt from an Anon on tumblr (my url is sassbutt-casbutt) I really wish I had more time to write the story but I did the best I could with the limited time I had. Thank Heavens for Francesca my savior when it comes to editing! Okay well enjoy the fluff!
Prompt
Dean comforts Castiel during a storm in the bunker
Castiel was sent running from the kitchen to cower in his room by a loud crack of thunder. He had experienced storms, even created them, before. He used to sit on peaks of hills and listen to rolling cracks of thunder, and watch lightning strike across the sky. It was entirely different this time; he was no longer an angel of The Lord. He had fallen, his grace was gone, and, frankly, he was terrified. It was a feeling he had only experienced a few times in his life. His grace almost acted as a buffer for the very human feeling of fear. Now, with his new found humanity, he no longer had the safeguard of his grace. The terror strung tight in his stomach and clutched at his throat. Thunder was no longer a beautiful thing.
Castiel heard the padding of bare feet down the dimly lit hall. Judging from the steps and pace, it was Dean. The hunter peeked into the darkened room and scanned over Cas, worry creasing his brow.
"Heya, Cas. What's wrong?" Dean's voice was the only sound aside from the rapid rain slapping against the window and Castiel's rushed breathing. "Dude, you look like you just saw a ghost. Oh, shit—don't tell me some of the Men Of Letters stuck around?"
Dean sighed at the thought of never being able to escape the hunt; the transition from loving hunting to being tired of it was a strange change in character. Castiel looked over Dean's features; in the dim light of the room his eyes were strikingly green.
"N-No, as far as I know, we are alone." Then again, Castiel's senses were no longer as sharp as they once were.
Dean just nodded and started to step back into the hallway, until an explosion of thunder made Castiel nearly jump out of his skin. Dean raised an eyebrow at his reaction and studied him intensely.
"D-Dean? Would you mind staying here for a minute?" Castiel's voice was low, almost broken. He had learned over the years that Dean was not the kind of person to hold a full-grown man, least of all an ex-angel of The Lord, through a thunderstorm. But Dean had always managed to surprise him since the day he met him.
"Sure." Dean waited a moment before walking over to the bed. "Are you scared of thunder, Cas?"
Castiel looked down at his hands, ashamed. "It seems so."
"Hey, it's cool. It used to have to sing to Sammy during thunderstorms when he was little," said Dean understandingly.
"I am increasingly older than Sam."
"Everyone has fears," said Dean matter-of-factly. "Sam hates Tuesdays and I'm no fan of dogs."
Castiel felt slightly better, but still very discomfited. Even though he knew very well what thunder was, the vast power it now held over him was chilling. "I see," he said, studying Dean's face and wondering where this softer side had come from. Clearly, the bunker was changing him in more ways than one.
"Hey, why are you scared of storms now? I mean, I remember a time when you used to burst into rooms with your very own clap of thunder!"
Castiel frowned at Dean's question. Why was he scared? "It is incredibly different now. It seems I don't like loud noises. I guess it's the first time I have felt at the mercy of the elements. I can no longer shoot the lightning out of the sky or fly at the speed of sound. I am weak." Castiel bowed his head and Dean opened his mouth as if to respond, but found he had nothing to say; he had never fallen from such power.
"Hey, you may not be a kick-ass angel anymore but you sure are a kick-ass human. I mean, you think Sammy can speak Japanese?" Dean finally said, trying to lighten the mood. The small smile that danced on the edge of Castiel's lips showed it was working. But just as quickly as the smile appeared, it was gone with the boom of thunder that shook Cas and sent him a few inches into the air.
"Do you want me to stay with you tonight?"
Castiel's eyes scanned Dean's face. It took some restraint not to yell yes; instead, he slowly nodded his head and pressed his shoulder to Dean's.
"Okay, come on. Let's lay down." Dean was already dressed in sweats and a white undershirt. He crawled to the head of the bed and pulled back the comforter, beckoning Castiel to follow suit. "Well, come on, now."
In that moment Castiel fully realized the remarkable changes Dean had gone through in the five years they had known each other. He had once looked at Castiel with annoyance and anger, but those expressions were now replaced with a comforting smile and warm eyes.
Castiel wrapped himself in his blankets and pressed himself into Dean's side. Another crack of thunder shook the bunker and drove into Castiel's core. It was nothing like diving into Hell or marching into battle, but before he knew it, wet tears were streaking down his cheeks into his pillow. Soft, muffled whimpers caught Dean's attention.
"I've got you," he said, pressing his nose into Castiel's thick black hair and inhaling the scent of cinnamon as he hugged him tightly.
"I'm sorry, Dean," Castiel croaked out.
"Hey, how many times have you watched over me? About time I returned the favor."
The smile crept back onto Castiel's face and he pushed himself deeper into Dean's safe grip.
The storm continued outside, but the fear slowly drained from Castiel. Dean held him securely in his arms, and the overwhelming power of the elements held nothing against the soft, hum of Dean singing "Hey Jude." In that moment, Castiel realized exactly where his family was.
I hope it wasn't too bad! Thanks again for reading! Comments and constructive criticism is always greatly appreciated!