It starts when Dean notices Cas' hands, and once he starts noticing them, he doesn't really, well, stop noticing them.
It's one of those guilty fixations that grounds itself in an initially harmless thought, maybe simple and fleeting in structure--Cas has nice hands--but has two unfortunate repercussions: one, Dean comes to the quick and unwelcome realization that that's not the type of platonic thought you have about your platonic very male, very ex-celestial friend; and two, once it starts, it absolutely does not stop for anything. Not even for the valiant attempts of a singular Dean Winchester.
Because once it starts with the hands, it's the other things, little things Dean tries to convince himself in vain he absolutely does not notice, like the way Cas' eyelashes droop sleepily when he's curled up reading on the couch, slowly blinking away the tufts of dust that curl up from the old pages, or the way Cas likes to wear socks to bed and usually loses one by the time he comes to breakfast, or the way Cas sings, not unpleasantly, in the shower at 7:30 in the morning when he thinks no one can hear him.
But yes, it starts with the hands, Cas' stupid, slender, farmer's tanned hands, in the kitchen on a random Saturday morning. Cas has taken to strange habits and phases in his humanity, between television and quilting and journaling and most recently cooking, and Dean stands in the doorway with a half-empty beer bottle dangling loosely from his fingers as he watches Cas work on some obscure type of omelet.
"Does this make you Julia Child?" he asks with a smirk, and his grin deepens when Cas responds with the expected, perplexed frown.
"I do not know who that is," Cas replies, half-distracted, "but I can only assume she is an advocate for the culinary arts."
Dean snorts and takes a sip from his beer, pocketing one of his hands. Cas has his sleeves rolled up to his elbows, and he applies to cooking the same methodical precision to which he applies everything else; his brow slightly furrowed, eyes serious but his mouth strangely relaxed.
Cas is dicing onions, the quiet chop of the knife against the cutting board the only sound in the amiable silence, and that's when it happens. Dean's eyes drift downward, toward the nimble way Cas' fingers are moving on the cutting-board, and thinks, Cas has nice hands.
It should've slipped in and out of Dean's subconscious radar without notice--it's not the first thought like that Dean's had about men, particularly Cas, but there must have been some sort of glitch, maybe due to the alcohol, because for a brief and betraying lapse of judgment, Dean imagines what those hands would look like on him.
Suddenly Dean's throat is dry and his eyes are tracing up the slender lines of Cas' tan forearms--why the hell is he so tan? Has he always been so tan? Dude's freakin' Dracula, barely leaves the bunker except to go to the farmer's market with Sam and cruise the Pimpmobile, how is he tan?--to the graceful bob of his shoulder as he puts his arm into cutting the onions with that same endearing, annoying focus that he had when smiting demons or watching The Breakfast Club for the first time.
Dean blinks and Cas is looking at him expectantly, eyes imploring--he'd asked a question that Dean hadn't heard.
"Er," Dean attempts. "What?"
"I said," Cas says slowly, and with great satisfaction. "Does that make you Julie?"
He looks incredibly pleased with himself for catching the reference, obviously expecting Dean to be pleased too, but Dean stares at him blankly. Julie? Who's Julie? Had they been talking about a Julie?
"Sam needs me," Dean blurts, because hey, that's always relevant, and Cas frowns after him as Dean practically flees the kitchen.
As usual, when Dean has some sort of belated revelation about himself, Sam is not far behind him. And again, as usual, his brother broaches the subject with all his admirable tact and grace.
"Saw you checking out Cas today," Sam says two days later, leaning back in his chair at the kitchen table and grinning triumphantly.
Dean, the picture of self-restraint, absolutely does not spit-take his drink. "You--what now?"
Sam folds his arms across his chest in that self-satisfying, smug way that Dean always hated as a kid because it inevitably meant he was about to get schooled. "I. Saw you. Checking out Castiel today."
"Are you high?" Dean snaps, and there's a hot, prickling feeling creeping up the back of his neck because honestly, he's not entirely sure he can deny it, depending on what Sam saw, how he interpreted it. "What the hell are you talking about?"
"Cas was washing his car today, yeah?" Sam says. "Then there was you. Just like. Watching him. From the front steps."
"I was not."
"You were. For a straight five minutes. You didn't move at all. You completely blue-screened, man."
"I was nature-gazing. I don't know. Shut up."
"You," Sam echoes, his voice flat and incredulous. "Nature-gazing."
"Yeah, dude. It's respectable. Didn't you ever read Thoreau?"
Sam raises one finger. "Don't try to distract me with literature. It never works."
"It always works."
"Name like, one plant ever, Dean."
"Oak. Maple. Marijuana."
Sam softens and leans inward; Dean leans back, because that's Sam's usual body language for initiating some sort of intimate conversation, to which, in its current context, Dean would probably prefer an acid bath.
"Dean," Sam says, the teasing gone. His eyes are wide and earnest. "If you like Cas--" At Dean's loud protest, Sam cuts him off quickly and says, "If you like Cas, and I'm not saying you do, I just want you to know that it'd be fine by me."
"I know it'd be fine," Dean says, flustered. "I don't. I'm not." He gives up, trying not to appear as floundering as he feels.
Sam rolls his eyes, not unkindly. "Dean, we stopped an apocalypse. Multiple apocalypses." Sam frowns. "Apocalypsi? Whatever. We've been through a lot of shit together. This is nothing. Actually, this is a good thing. We don't get too many of those. Don't hold yourself back from it on my account."
With a small quirk of his mouth, Sam leaves Dean to think about that for several more minutes. The thinking is followed closely by downing more alcohol and not-so-gracefully avoiding Cas when he comes in from outside drenched in suds and sweat, his dark hair plastered in damp curls to his forehead.
"I like washing cars," Cas tells Dean as he moves to the fridge to dig around for the cantaloupe (Cas has like, a thing with cantaloupe). "It's strangely therapeutic."
"Yeah," Dean croaks, diverting his eyes from how Cas' thin shirt is clinging to the taut line of his back with sweat. "Thera…yeah."
"Are you alright, Dean?" Cas turns with a frown, his eyes dropped as he wrestles with saran wrap. "And don't just say you're fine."
"I'm fine. I'm gonna shower," Dean says, standing abruptly from the table with a loud scrape of the chair's legs against the floor. "You should too, because you're--well, I mean, you don't have to shower, it's just, I usually like to after--"
Cas has given up on the saran wrap and is staring at him in confusion.
"Yeah," Dean says, and bails again.
If Cas notices Dean's strange (and semi-miserable) behavior, which he most likely does, he doesn't comment on it throughout the next week. Cas starts hunting with them again, actually, which provides more than enough distraction for all of them--Cas spending long hours in the bunker's firing range, Sam giving him various pointers, and Dean silently fretting.
He's absolutely certain Cas isn't ready for hunting until he actually sees Cas standing over the beheaded corpse of a vampire in Sioux Falls later that week, shoulders heaving, grinning triumphantly and half-wildly as Sam pats him on the back in congratulations, blood flecked on his face and mouth, a smear of gun oil on his cheekbone--
Maybe Dean isn't ready for Cas hunting. This is getting ridiculous. It's pathetic. Nicholas Sparks would have a fucking field day. Dean's full-on miserable.
"This is such bullshit," Dean says to Sam without explanation on the way home, with Cas curled up asleep in the backseat, and Sam doesn't seem to require elaboration.
Dean makes up his mind that car drive home to talk to Cas about--whatever this [insert vague hand gesture] was--but Garth calls that night with an unexpected werewolf case in Tennessee and after a short and restless sleep, they're on the road again, Dean and Cas playing tag with their gazes in the rearview mirror.
They split up once they reach the werewolves' place, which is apparently an abandoned factory for children's stickers or some shit. Sam takes off to track the single girl werewolf, whereas Dean and Cas band together to take the male, and Cas stays close to Dean's side throughout, his breath soft on Dean's arms, causing goosebumps to pebble on his skin, and goddammit, it is so not the time to get distracted.
The male werewolf, a scruffy, brawny guy in his mid-thirties, attacks them not much later from behind some old barrels, and Dean and Cas spring away from each other; Dean's already swinging his gun around, aiming, and his vision whites out when he sees the werwolf is already on Cas, and there's a loud shrill bang before Dean smells the sharp kick of the gun and realizes it was him and that he'd also yelled Cas so loud that his ears are ringing tinnily.
The werewolf had collapsed on top of Cas at the hit and Dean throws his gun to the ground and is racing forward, his heart thundering in his ears, and he pushes the werewolf's corpse off of Cas and says his name over and over again, takes his hand and squeezes, trying to figure out in his panic if the blood drenched in Cas' clothes is his or the werewolf's, oh Jesus, oh Jesus, Cas--
Cas blinks dazedly a moment later, looking stunned as he stares up at Dean. "Dean? Did we--?"
"Holy shit," Dean breathes and hangs his head a moment, lets all the tension in his body go slack with relief, and it takes him a moment through the receding panic to realize his thumb is stroking frantically over Cas' knuckles. "Thank…thank Jesus…Cas, you cannot keep doing that to me, shit."
Cas squirms and squints, still looking half-pained. His hand shifts in Dean's grasp but Dean for some reason can't let go; he's got Cas in a death-grip, which Cas belatedly notices with a disoriented look at his right hand.
"You're holding my hand," he says, as if to inform Dean, maybe to tell him to let go.
Dean can feel their pulses together, that's how tightly he's gripping Cas, and without thinking, without meaning to, he twines his fingers with Cas' and locks them, tightly. "Yeah." He clears his throat. "I mean…if you're into that kind of thing?"
It's a stupid thing to say, but it's an invitation, a beginning, even if an inarticulate one. They both know it. Sparks is somewhere writing his bestseller. Fireworks are going off. They're holding hands like teenagers, and here's Dean, hearing the freaking hallelujah chorus in his head.
Cas' whole face softens; he smiles. He locks his fingers with Dean's, tighter, and squeezes back.