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“Did you have to touch that thing? Jesus, Sam!” Dean paces the motel room, running a hand through his hair as doomsday scenarios form in his mind, each more serious than the last.
“I didn’t mean to,” Sam says snappishly, sitting on one of the beds and wringing her hands. “I just wanted to see what it was.”
“You’re supposed to be smarter than that,” Dean says. “I mean, fuck. How long have you been a hunter? You know not to fucking touch something when you don’t know what it is!”
“You’re one to talk,” she cries, shooting Dean a dirty look. “You always go into things half-assed!”
“Well, I’m not the one who has to get knocked up in the next day or die,” Dean says snidely.
“It’s not like we can change anything now,” Sam snaps, standing up and smoothing her shirt. “We’re just gonna have to bite the bullet and go for it.”
“Whoa, whoa, whoa,” Dean says, holding up a hand palm out in Sam’s direction. “We? Who said anything about we?”
“I’m obviously not going to go out and fuck some random guy when I know I’ll get pregnant!” Sam shouts, throwing her hands in the air in exasperation. “It has to be you! If I don’t appease this stupid goddess, then I’ll die, and we all know how well that turned out last time!”
“So your solution is to fuck your brother?” Dean shoots back. “Jesus, Sam!”
“Yes!” Sam yells. “Compared to the alternative, then yes! I’ll fuck you over anyone else.”
“Forget it,” Dean snarls. “I’ll just go out and find someone. It can’t be that hard.”
Sam turns her puppy-dog eyes on Dean, obviously trying another tactic seeing that her angry reasoning hadn’t worked at all. “Please,” she says softly. “It hurts. I don’t want anyone else.”
And now that Dean is paying a little more attention, he can see that Sam is squirming slightly where she sits on the bed, her legs pressed firmly together. Her pupils are blown wide and she’s breathing heavier than perhaps she would normally, and holy fuck, she looks like a fucking advertisement for sex. For half a second Dean is convinced, remembering all those times he looked when he wasn’t supposed to, noticed her in a way that he shouldn’t have.
And then he realizes that she’s his fucking sister, for Christ’s sake, and he isn’t going to touch her like that. He fucking won’t.
“No,” he shoots back. “N. O. No fucking way, Sam. We’ll just have to find another way.”
“There is not other way,” Sam says angrily. “We’ve been over this! I’m not sleeping with a goddamn stranger. Stop being a pussy and just get over here already.”
“I’m not going to knock my sister up, Samantha,” he says.
“Tough shit,” she responds, standing up and advancing on him. He takes three steps back, running into the wall, but she doesn’t stop moving.
“Sam,” Dean says warningly.
“Shut up,” she replies, getting right up in his space. “You know I’m right.” Then, without a so much as a warning, she reaches up and pulls Dean’s lips down to hers. He’s too shocked by the action to be anything other than unresisting, and Sam’s taking no prisoners. She kisses hard, desperately, and he opens his mouth unthinkingly under the onslaught. Her lips are soft, if a little chapped, and as soon as she can, she’s fucking her tongue against his and rocking into his space, her soft belly rubbing against his crotch.
When it finally catches up to Dean what he’s doing, he breaks the kiss with a, “What the fucking fuck, Sam?” but she’s having none of his bullshit. Stepping on her tiptoes, she puts her weight behind her hands and pulls his head down again. Dean wants to stop this, he really does, but jesus, she’s a fucking awesome kisser, and she’s sucking his tongue into her mouth and she tastes like fucking heaven, and Dean’s just not wired to ignore something like this. With something close to a growl, he cups his hands on her thighs and pulls her legs around his hips.
She makes a pleased noise in the back of her throat and locks her knees, throwing her arms around Dean’s neck. There’s something heady in the air, something entirely intoxicating, and Dean’s head swims with it. The way he’s holding her puts her crotch in direct alignment with his, and she’s grinding against him--there’s no other word for it--just fucking him through two sets of jeans. He’s getting hard from the press of her body, from thinking about sliding into her, about filling her up, and he moans again, louder, the noise swallowed up by Sam’s mouth.
This time, it’s Sam that breaks the kiss, breathing hard and dragging her lips along the curve of his jaw, leaving little suckling bites on his skin.
“C’mon, Dean,” she whispers. “You know you wanna.” And Christ help him, he fucking does, wants to fuck into his sister and make her heavy with his baby, and jesus fuck, he should be going to hell for thinking it.
Sensing his hesitation, Sam lets her legs fall back to the floor and then slides down onto her fucking knees.
“You need a little help here?” she asks breathlessly, cupping his erection through his jeans. Dean certainly doesn’t whimper, but it’s a very close call.
“Sammy,” he groans as she leans forward and nuzzles his cock, closing her lips around it through the denim, making his jeans wet with her saliva. She pulls on the zipper with her teeth while simultaneously unbuttoning his pants with her hands, and then she’s pulling down his jeans and his boxers and his cock springs free, impossibly hard and ready for her. She doesn’t even hesitate, just sucks it down like she’s always wanted to, closing her lips around the head and pushing her tongue into the slit.
Dean can’t help it; he fucks forward into the slick heat of her mouth, and she opens his jaw further and lets him in, her tongue rubbing against the bottom of his dick, and jesus, oh my fucking god in heaven, it’s so fucking good, Dean could die from it. She’s humming, and holy fuck, she’s unbuttoned her own pants and wormed her hand into her underwear and Dean can see her hand moving, rubbing at herself as she sucks him off. She’s humming around his cock like it’s the best thing she’s ever had, and Dean wants to come down her throat so fucking bad, coat her face with his jizz and rub it into her skin, but he can’t, he fucking can’t, he needs something more.
She pulls off with an obscene pop and looks up at him, using her hangdog expression to great effect. “Dean, please,” she begs, and that’s it, that’s fucking it. Grabbing at her arms, Dean pulls her into a standing position and then turns her around, forcefully slamming against the wall. Instead of making a pained noise, she kicks her pants off and then her underwear.
“Gonna fuck me, Dean?” she asks desperately. “Gonna knock me up? God, I fucking need it, please.”
“Shut the fuck up,” Dean growls, hauling Sam’s legs up once more. He barely gives her any time before he’s pushing into her, right into the wet, tight heat of her cunt. He wants to give her time to adjust, he really does, but fuck, that’s all she wrote, because he can’t stop himself from thrusting into her again and again, starting a punishing rhythm.
Not that Sam cares at all; she’s practically screaming. “That’s it, oh God, yes, yes, Dean, fuck.”
“Take it, fucking take it,” he says, breathing into her ear as she scrapes her fingernails down his back. “I’m gonna make you so full, Sammy.”
“Yes, Dean,” she cries. “Yes, yes, fucking fuck me, please,”
And Dean can see it now, see Sammy heavy with his baby in her belly, her tits full of milk for his kid.
“Fuck, Sammy,” he groans, and she’s coming and he’s coming, spurting up inside of her, her cries loud in his ear. But that’s not it, that can’t fucking be it, because Dean doesn’t feel satisfied after he’s come. He just wants more, wants to fuck her through the fucking wall into the next motel room, and he’s not getting soft but harder.
“What the fuck,” he groans, but he hauls her off of the wall, slipping out of her with a slight squelch. He throws her onto the mattress and is on top of her before she’s even stopped bouncing, pushing in again. He kisses her as he thrusts this time, messy and frantic, and her moans don’t ever stop, just get louder. She comes before he does this time, her pussy fluttering around his cock, and that only makes him want more, want it harder.
“Gimme your baby,” she pants in his mouth, still moving her hips in time with his. “I want it. God, I fucking want it, Dean, c’mon.”
“Fuck,” Dean snarls, and he’s coming again and the pleasure’s white hot and almost unbearable. And he’s still not fucking done, fuck.
**
Five orgasms later, and Dean is literally fucked out. They’re lying on the bed, which is utterly ruined from the night’s activities, and Dean is never moving again, not if he can help it. Sam shifts sleepily next to him, pillowing her head on his shoulder.
“You know that this means we’ll have to get a baby seat for the Impala,” she murmurs, pressing a light kiss to his skin.
“Shut the fuck up,” Dean says, and her light giggles are the last thing he hears before he falls asleep.