As per usual, I don't own the boys. I just make them do dirty thing for my own pleasure.
People generally think it's Dean with the dirty mouth. And sure, he can talk a good game, flirt with the best of them, but he can't get people squirming in their seats like Sam can. He can't turn someone on with a few cleverly placed words in a husky whisper, breath washing tantalisingly over the skin as he promises things that'd make a whore blush.
And Sam knows he has that effect on people. He rarely uses it, doesn't like to take advantage of it, so it's Dean the guys and the girls in bars go for, Dean with the easy smile and easier wink. But every so often, Sam will let his libido take over, and Dean pities the poor sucker who falls under his gaze.
Of course, it's usually Dean that Sam focuses on, but a little self-pity never hurt anyone too badly.
They're in the middle of interviewing two witnesses, teenage girls from the same school as the last boy who was killed. Dean's fairly sure the dead guy fucked both of them, but they're staying tight-lipped about the whole thing. They've got no information beyond what he and Sam already know - or, if they do, they're not sharing it.
Sam's getting bored, understandably; fidgeting in his seat and glancing out of the window impatiently. The two girls both latched onto Dean as soon as he slid into the seat oppostie them, hardly sparing a glance at his brother, and Sam's been sitting silently for the past half-hour. Still, there have been plenty of times that Dean's been bored with whatever research Sam's got him working on, so he figures a little payback wouldn't be too cruel.
And then, inevitably, it backfires on him quite spectacularly.
The first time Sam leans over to tell Dean in a low voice that these two have nothing else, Dean, come on, let's go, Dean thinks nothing of it. If anything, it makes him more determined to stay talking to the teenagers for a long as possible, because it'll piss Sam off, and maybe if he's lucky Sam'll fuck him when they get back to the motel. Sam's a kinky bastard when he's angry, and it's been a while since Dean felt that rush that comes when Sam dominates him.
So he shoots Sam a lazy grin and turns back to the girls, asking them about their math class for what seems like the thousandth time. Sam grits his teeth in frustration, digs his nails into Dean's leg, and leans closer.
"I'm so fucking hard right now," he whispers, voice dipping down a few octaves until it's nothing more than a low purr in Dean's ear. Dean tenses, swallows roughly, and lets his gaze drop to Sam's eyes, because yeah. That was unexpected. And hot.
Sam grins, catlike, and shrugs slowly. Dean forces his eyes back to the girls, who look confused, and sends them a weak smile, shaking his head slightly at his brother. Not now, Sammy.
The girls pick up their story, their eyes flickering over to Sam every so often, taking in the smug expression that tells Dean that Sam can see his groin, see the tent in his jeans.
"Y'know, if I shut my eyes and think real hard, I can see you stretched out on the bed underneath me. You look so fucking pretty like that, mouth all fucked out and lips swollen, completely naked. All for me, Dean. So pretty for me, so desperate for me."
Dean has to choke back a groan at Sam's words, at the fingers stroking teasingly up his lower thigh and the laughter puffing out over his ear. It takes a moment for im to compose his face back into the slightly bored expression it had been a moment earlier, and then he's back with the girls, ignoring his brother.
Fairly predictably, Sam doesn't like that, moves his hand higher to keep Dean's attention on him.
"God, Dean, you're as hard as I am right now, aren't you? Does it turn you on, the thought of me fucking into you? I won't be gentle Dean, I won't treat you like some princess. I'll fuck you like a man, hard and fast and so deep you'll feel it for days." Dean coughs, clenching one hand on the edge of the table, tries to focus on what the girls are telling him - something about their prom night, about how the guy had seemed off - but it gets harder and harder as Sam keeps spilling filth into his ears.
"What if I jerked you off right here? If I just unbuttoned your jeans and pulled you out, kept going until you came all over my hand? Wouldn't you just love to see their faces, Dean? Do you think they'd want to join in?"
One the of the girls smiles prettily just as Sam finishes his question, and Dean can feel Sam's grin against the skin just beneath his ear.
"She would, God, look at her. She's almost as much of a slut as you are. I bet she'd love it, she'd want to watch as I fucked you into the sheets, or into the wall, or the floor. Can you hear the noises she'd make, Dean? Would they be as pretty as the noises you make for me?"
And God, now Dean can see it when he closes his eyes, can see Sam over him with that smile, that teasing, triumphant smile because he knows he's winning now.
"I could make it slow, if that's what you'd prefer. I could finger you open nice and careful, until you're begging for more, for all of me. Is that what you want? Want to beg for me, Dean? You look so hot when you beg."
Sam's tracing circles over his cock now, and Dean knows he'll do it, he'll pull him out and jerk him off in the middle of the cafe if he has to, whispering promises into his ear the whole time.
When Sam blows out gently, tells Dean how he'll slide his tongue inside after his fingers, suck until he can't taste anything but Dean, it's easy to rise to his feet and shoot the girls the usual thank you for your help, goodbye spiel.
Sam grins when they reach the car, laughs when Dean growls that he's gonna have to deliver now.
"I'll make you scream, pretty boy," he replies, pulling Dean up into a messy kiss before sliding into the Impala.