Here is a small, silly little thing from alexadean's "SPN SLEEPY TIME MEME!".
Prompt from orbiting_saturn: "Crazy!Cas doesn't need to sleep, but he likes to. He also likes to use Sam as his bed." Spoilers for 7x22 and 7x23.
"Dude," Dean says suddenly, sitting up to peer over the edge of the table. "Is he here again?"
"Uh—" Is it bad that Sam hadn't even noticed? Castiel's head is warm and heavy on his thigh, Sam's fingers frozen in the motion of carding through his hair, and for the life of him he cannot remember when Castiel showed up. Or when he'd started petting him.
Sam's sitting on the bench seat in the motel kitchen's tiny nook, and Castiel has somehow curled his body into the small space leftover, knees tucked to his chest and forehead pressed to Sam's stomach.
He starts to draw his hand back and Castiel makes a sleepy, petulant sound of disapproval, butting up into his retreating fingers, and Sam can't quite mask a smile as he obediently stritches through the short, soft hair just behind his ear.
Dean's face is kind of hilarious, a cross between sour grapes and maiden aunt as he falls back into his seat. "Oh, sure, pet the crazy angel," he says, throwing up his hands. "Not like we've got anything better to do, like, I don't know, find a way to stop the Leviathans from taking over the planet."
"I think I can manage to multitask, Dean," Sam says, turning a page and playing absently with the stubborn cowlick at the crown of Castiel's head.
"I need a fucking drink," Dean grumbles, and shoves away from the table to stalk towards the grungy fridge and its endless supply of cheap, awful beer.
"Y'know, pets have been scientifically proven to lower blood pressure," Sam says, turning another page.
"So has alcohol," Dean growls. "And alcohol doesn't show up naked and covered in bees on my baby."
The first time Sam catches Castiel sleeping on him is only a week or so after the infamous Covered in Bees incident, which may in fact explain why it's Sam, rather than Dean, who wakes up with an angel slumped over his back. It can't be comfortable, but the look on Castiel's face is pure bliss once Sam's craned his head around to see who exactly is crushing him into the mattress.
Dean's snores from the other bed continue uninterrupted as Sam whispers, "Um. Cas?"
The angel's still in his asylum scrubs and trenchcoat ensemble, and he's stretched out horizontally across the bed, face down with his arms outflung and hanging over the edge. He looks for all the world like he's done a belly-flop onto Sam, although Sam's pretty sure he would have felt that. Probably. If anyone's capable of executing a stealth belly-flop, it's this new, clinically insane version of their guardian angel.
"Cas?" he tries again, a little louder, and this time the angel's eyes slit open.
"Yes, Sam?" he says, and doesn't sound sleepy at all.
Sam's getting a crick in his neck from holding his head a such a weird angle, looking back over his shoulder at Castiel's politely inquiring expression. "Was there something you wanted?" he asks finally, because just blurting out "Why the fuck are you sleeping on me?" would be rude.
"Did you know that cats sleep between sixteen and twenty hours a day?" Castiel responds. "That's eighty percent of their lives. I wonder what they dream about."
Sam sighs. It's about time for his morning run anyway, so he slides out from under Castiel and repositions him so that all his limbs are on the mattress. Castiel blinks up at him with an almost wounded look, and Sam gives the angel an awkward pat on the head, because what else can you do when a crazy person shows up in your bed and starts talking about cats?
It makes Castiel smile, which is still a very weird and strange phenomenon. But Sam thinks it may be starting to grow on him.
"There's food in the fridge," he says, slipping his phone in his pocket and starting his stretches. "You could—I don't know, make yourself some breakfast."
"I don't eat, Sam."
Sam sighs, and opens the door to birdsong and the rosy Tennessee dawn. "Make Dean something then. I'll be back in a half hour, okay?"
"Okay, Sam," Castiel says peaceably.
Three miles in, Sam gets a text from Dean that says /WHY TH FCUK IS THERE AN OMLET WITH JELLY BEANS AND FRNECH FRIES ON MY PILOW/ and has to stop and lean against a tree, he's laughing so hard.
Castiel likes sleeping in the sun almost as much as he likes sleeping on Sam, and the concordance of the two never fails to draw the angel in. This time they're in some podunk town's public library, and Dean's watching with narrowed eyes as Castiel insinuates himself between Sam's book and Sam.
"Why the hell does he do that?" he asks, not for the first time, and Sam shrugs and puts an arm around Castiel's waist to hold him steady. The noise Castiel makes is a beatific purr, and he tucks his head more securely under Sam's chin. The rough prickle of his stubble scratches slightly at the skin there before his body goes lax against his, limp and languid in the warm fall of summer sun through the window.
"Dude," Dean says, face pained and one eyebrow jacked high. Sam shrugs again, and returns his attention to his book.
"Seriously, though," he says once, late, late into another long and fruitless day of research and frustration. They're going to break into a Catholic ossuary tomorrow, and Dean had said something snarky about beauty sleep before disappearing into the parking lot. He'd taken Bobby's flask with him, and Sam imagines they're out in the Impala, just driving. It's too much to hope they're actually talking.
"Mmph?" Castiel says agreeably, head resting on Sam's chest. Sam rubs firmly into the muscle at the base of his skull and the angel moans and arches into the touch like a cat, completely unselfconscious. His fingers flex and knead where they're curved around Sam's shoulders. He wouldn't go as far as to call Cas a pet, and it was mostly a joke when he'd said it to Dean, but touching Castiel like this really does calm him down.
"Why? Why the—you know," he says, as Castiel raises his head and rests his chin against Sam's sternum, staring at him from less than a foot away. "The sleeping on me. And stuff." Yes, Sam is the eloquent Winchester, wouldn't you know it?
Castiel's silent for so long that Sam gives up hoping he'll answer, and settles more fully back against the mound of motel pillows, prepared to make a night of it.
"You're very comfortable," Castiel says, and it's so sudden Sam jerks.
"Comfortable?" he says dumbly, because—what? There isn't a soft edge on him. And with the breakage of walls and the guilt and the amount of suffering they've caused each other, he's pretty sure Castiel can't mean that in a metaphorical sense.
"Yes," the angel says, his intense stare boring into Sam. "Comfortable."
And with that, the conversation seems to be over. Castiel resettles himself with a small hum, body draped over Sam's like a heavy, warm blanket, and closes his eyes.
After a moment, Sam reaches over to turn out the light.