When one had spent the better part of eternity as a celestial being, adjusting to life as a human with little to no transition was…difficult.
Things that came naturally as a human like sleeping, eating, and regular hygiene upkeep proved to be a serious challenge to a certain fallen angel, and Sam and Dean weren't always forgiving of things like wandering around the bunker at daybreak, or forgetting to shower for a few days.
So it took a while to grow comfortable in the skin that didn't used to be his. He supposed that he had grown pretty used to wearing Jimmy's vessel at that point, but it was still a bit surreal to look in a mirror and remind himself that this was actually his body now; not just a vessel that he was occupying.
It wasn't until a particularly grey and drizzly Wednesday in October, however, that Cas fell victim to an extremely unexpected and unwanted aspect of human life.
"I'm ill." He announced that evening to a very unimpressed Dean, who was leaning against the doorframe to the room that now belonged to Cas.
"Really?" Dean said in a tone that Cas suspected held sarcasm, though he still had difficulty picking up on that. "Because it wasn't like you've spent the entire day whining about how stuffed up you are, and how much your throat hurts, and how damn freezing it is in here."
"It is cold." Cas replied defensively, pulling the blanket he was bundled up in tighter around his shoulders.
"Yeah, because you're sick. And will you stop looking at me like the world is ending? You act like nobody's ever had a friggin' cold before."
"I've never had a cold before." Cas peered grouchily across the room at Dean, feeling disdainful at the other's lack of sympathy.
But Dean's expression softened at Cas's words, and he finally pushed off of the wall, striding over to Cas's bed.
"Sammy left to get you some soup and ginger-ale." Dean said, taking a seat at the edge of the mattress. "It helps when you're sick." He added at the bemused look on Castiel's face.
"I'll…have to thank him when he gets back." Cas replied, a little stiffly. He found it difficult to be grateful of anything when he was feeling so terrible. He just wanted to wrap himself in every blanket in the bunker and spend the next week in bed.
"Damn, you're a grouch when you're sick, aren't you?"
Cas opened his mouth to give back an angry retort, but Dean distracted him from his indignation by grabbing at Cas's blanket and wrapping it around his own shoulders as he slid onto the mattress and tugged Cas close against his side.
Cas protested. "Don't touch me, I'm ill!" He groaned, trying with little success to squirm away from the other's touch. "You'll catch it too and then you'll be sick."
"I'll live, because I'm not a big friggin' baby like you are."
"I'm not an infant." Cas grumbled, but he quickly dropped his attempts to shove away from Dean; the other man's body heat was just too inviting.
He rested his head against Dean's chest, letting Dean pull him in tighter. He instantly felt better.
Well, maybe his cold didn't feel any better, but a good chunk of his grouchiness had certainly ebbed away.
It was hard to be angry when he got to listen to the even pace of Dean's heartbeat, and feel the man's fingers brush comforting circles over his shoulder.
"You should sleep, Cas. That's probably why you got sick in the first place—You're always staying up all night."
"I have a headache."
Dean sighed in clear exasperation and paused for a moment before speaking up again. "When I was a kid my mom used to sing 'Hey Jude' to me to get me to sleep."
"Who's Jude?"
"It's a song, Cas. The Beatles."
Cas stared quizzically at Dean, trying to make sense of his almost cryptic sounding words. "I don't understand…what do insects have to do with music?"
"Cas," Dean groaned in clear frustration. "The Beatles are a band. They wrote a song, and it's called 'Hey Jude'. How the hell do you not know that? Actually, you'd probably like The Beatles. Maybe I'll have you listen to them sometime…"
Silence fell between them again, and Cas was just starting to ponder on the relevance of Dean's words when he found the other man's lips barely brushing against his earlobe, and his voice was soft as he sang,
"Hey Jude, don't make it bad. Take a sad song, and make it better…Remember to let her into your heart, then you can start to make it better…"
Cas didn't know the lyrics. It was a song he had never heard before, but the words held comfort and warmth coming from Dean's voice.
"Hey Jude, don't be afraid, you were made to go out and get her…the minute you let her under your skin, then you begin to make it better…"
Cas never knew that Dean could sing. He had never heard the other try, but he supposed it wouldn't matter if the words Dean was murmuring into his ear were out of tune or not; it wouldn't have stopped how comfortable and at home right at that moment.
"And anytime you feel the pain, hey Jude, refrain, don't carry the world upon your shoulders…For well you know that it's a fool who plays it cool, by making his world a little colder…nah nah nah nah nah…"
It was amazing, really, how quickly Dean could send Cas's insomnia whisking away with a few simple stanzas like that, because Dean had barely started up the second verse when Cas's eyelids were drooping, his face now pressed against Dean's chest, his heartbeat rhythmically lulling Cas in time with the singing.
He was somewhere floating between dreaming and waking when he remembered Dean's singing trail off into silence, but he was almost positive that the warm kiss pressed to his temple, right before he slipped completely out of consciousness, hadn't been a dream.