moonlettuce | MMoM Day 17: It's a perfectly natural and healthy biological function, SPN

Title: It's a perfectly natural and healthy biological function
Author: Claire
Fandom: Supernatural
Pairing: Dean/Castiel
Rating: R
Summary: In which Sam's trying to sleep, Castiel gets possessive and Dean just wants to masturbate.

Dean huffed quietly as he stomped to the Impala, muttering under his breath about freaky ass brothers too big for their boots. Who did Sam think he was, anyway? Kicking Dean out of the room just because Sam thought he was jerkin' off too loudly. Who the hell complained that someone was jerkin' off too loudly? So what if Sammy was trying to sleep. That's what goddamn pillows were for; to gently cushion your head while sleeping and to block out the sounds of your older brother whacking one off.

You'd think Sam had never heard Dean before. Hell, with the exception of Stanford, they'd practically shared a room their entire life, so Sam was probably the first person to ever hear Dean coming under his own steam. In fact, Dean knew Sam was. Knew it because Dean remembered Sam thinking Dean was ill and getting Dad out of bed to check on him because he didn't want to check himself in case Dean was gross and puking. Some gentle teasing (John) and a lot of mortification (Dean) later and Dad had suggested that it might be better to wait until Dean knew Sam was definitely asleep before starting his nocturnal activities.

The next day Dad had sat Sam down to give him The Talk, which had led to him staring wide-eyed at Dean and thinking Dean was a freak (some things never changed) and declaring girls were icky and he was never touching one as long as he lived (and some things really, really did).

It wasn't as though Sam hadn't done enough moaning of his own at times. With his oh, Jess and oh, Jo and oh, Ruby and oh, Hannah Montana (and Dean wasn't touching that one with a ten-foot pole) he'd kept Dean awake enough times to think Dean could get away with a few groans of his own.

But, no. One Jesus fuck, Cas screamed out and Sam was all I'm trying to sleep, Dean and stop whacking off to thoughts of the angel, Dean and for God's sake, don't you ever stop, Dean. It had been Sammy's you're making Jesus cry, Dean that had been the final straw and Dean had finally snapped.

Why? Is he pissed his brother's gettin' more action than he is, as well?

Which was apparently it for Sam, who had gotten out of bed, gotten Dean out of bed, manhandled him to the door and thrown him out of the room with his dick still his hand. Dean had stood there not knowing exactly what had happened when the door opened again. He'd just opened his mouth to ask Sam what the hell he'd thought he was doing when the Impala keys came sailing out to land on the ground and the door had shut again. Bitch.

Dean had been tempted to bang on the door until Sam let him back in, but it was two in morning, the clerk on the desk was bigger than Sam and Dean had no desire to be either beaten up or arrested. He just wanted to sleep. And jerk off. Mainly jerk off at this point, since his cock was still hard, even with the manhandling Sammy had done.

Luckily, it was summer and still relatively warm at night, and the Impala had pretty comfortable seats. It wouldn't be the first time Dean had slept in his baby, and at least he knew she wouldn't kick him out for jerking off in her.

"Hey baby girl," Dean murmured softly, running a hand over her bodywork before he open the door. "At least you love me." He sighed as he slid into the welcoming leather of her seat. Damn, he loved his car. Although totally not in that way, no matter what Sammy might think. Well, except for that one time, but Dad had just given her to him and Dean had gotten a little too excited about it. And then had had to clean her exhaust pipe with Sam's toothbrush.

Closing his eyes, Dean rested his head against the back of the seat and started pumping his cock, images of Cas running through his head. Cas looking badass as he smote demons. Cas captured by demons, naked and chained and oh so grateful when Dean rescued him. Cas dressed as a cheerleader, sparkly pompoms rubbing against--

"Hello, Dean."

"Gnargh!" Dean yelled in shock, eyes open and hand snatched away from his cock.

Cas was sitting in the passenger seat.

"Jesus, Cas, don't do that!" Dean said, his heart rate finally coming down to normal.

"I need to speak to you about the plan for the Seal in Cleveland, and since you're awake I thought now was as good a time as any."

Oh no. Dean was there, his dick was there. This was Dean time, not Stopping the Apocalypse, yay! time. "It'll have to wait a few minutes," he said, wrapping his fingers back around his still hard cock (little Dean just kept on going, no matter what) and starting to stroke.

"Well, I suppose. It's not as though saving the Seals and stopping Lucifer from bringing Hell on earth is urgent or anything." And damn Ruby for teaching Cas sarcasm, Dean thought. Er, damn her more than she already is, anyway.

"Good, then just sit there and look pretty. And if you want to throw in the occasional 'Give me a D' for authenticity, feel free," Dean added.

Cas looked confused. "Give me a-- Can you please stop doing that," he snapped, eyes on Dean's cock and following the movement of Dean's hand up and down.

"Why?" Dean threw in a little circular motion just to watch Cas's eyes roll as they tried to follow the action.

"Because--" Cas wrenched his gaze away from Dean's cock. "Because I'm finding your penis rather distracting."

Dean grinned, hand speeding up slightly. "You'd be surprised how many people have said that to me."

"I assume no one recently," Cas commented, cheeks starting to look flushed and eyes darker.

Dean's grin widened. Damn, his angel was hot when he was jealous. "Well, there was that cute waitress back in Maine, and the bar tender in--"

Dean never got to finish the sentence, the rest of his words cut off by the quiet growl coming from Cas, as Dean's hand was knocked away from his cock to be replaced by Cas's own.

"Mine," Cas said, and then his mouth was on Dean's, tongue lapping at Dean's lips and demanding entrance.

Dean arched into Cas's hand, tangling his fingers in Cas's hair and pulling him closer, grinning under Cas's assault. His car was badass (and running better than she'd ever been), his (admittedly kinda whiny at times) baby brother was safe back in the motel room and his angel was doing things to him that were illegal in at least seven states. Oh yeah, Dean thought, it's good to be me.