thank youuu for the prompt(s), dear!! inspiration struck on this one, so I did my best and I hope you somewhat like it!!
I went with Sam x Leviathan!Sam + noncon + feminization + humiliation, so beware if that's not quite your thing :)))
“Come on, open that cunt up. Lemme in,” the beast breathes into his ear, making his grip impossibly tighter, making Sam hiss.
He fought hard, but that creature has learned to read him long before it stole Sam’s face.
“Fuck you,” Sam snarls, struggles against the hold still, refuses to give in.
Sam knows torture, knows hatred, but nothing could have prepared him for the sight of his own grit teeth snarling at him, his own wild eyes staring him down, tripping him out in a way that makes his blood run cold.
The leviathan’s cock is relentlessly pushing into him, making him cry out and only spurring the beast on, he can hear its delirious cackle full of self-satisfaction over the ringing in his ears.
“I know what your body’s capable of, Sammy-Sam,” it groans, licks up Sam’s sweaty neck, smacks its full lips, “I know what you let those boys do to you in college, how you let them cunt you over and over again, so desperate to be accepted. I know how you give it up for big brother’s cock whenever he asks. So easy, Sam, you’re so. fucking. easy.”
Each word is backed by a hard thrust that’s scraping along Sam’s insides, but it doesn’t compare to the pain of being so known, the pain of having his most secret moments out in the open like this.
“There she is, lemme have it, atta girl,” it hisses as it finds his prostate and hammers into it, the pace so brutal it rivals Dean’s stamina on his best days.
Sam knows his dick is big, has known since he was a young teen. He’s heard it from multiple partners, has seen how swollen he leaves the cunts he blesses with a thorough fucking, has secretly asked himself just how much they must’ve loved it when they kept begging him for more despite the pain.
Now that he knows what it feels like to have it deep inside, turning him inside out, he curses everyone who’s ever come back for seconds.
It’s pure agony, the pain of an endless stretch with the hot pleasure of his spot getting pounded.
“Nghhh- n-no, fuck, stop-“
“You’re gonna come from this,” his voice tells him, deep and full of arousal, making Sam’s gut tighten reluctantly, “you’re gonna come on this cock and then you’re gonna go to back to big brother and tell him what happened. Tell ‘im what you did.”
“I d- didn’t-“
“You did, you tempting fucking whore. C’mon, give it up. You know you can’t escape this.”
When he comes, it’s with a wail of shame, the embarrassment so bone-deep he feels his heart pound at the thought of being the one to finally cut that monster behind him up, pay him back for all the humiliation he’s caused.
It’s the only thing that’s keeping Sam from taking up the knife and driving it through his own skin, just to forget that this was ever done to him.
The leviathan pulls out with a rough shove, chuckling nastily.
“As nice as this was, sweetheart, I can’t bring myself to finish. I’m not a fucking freak, after all.”
Sam is panting hard where he’s bent over the rickety table, and out of the corner of his eye, he can see the glint of his abandoned knife on the floor. He must’ve lost it when he was grappling with that thing wearing his meatsuit.
Grinning wide, he dives for it, feels the handle slip into his palm, and turns around to start slashing.
Where's that post I saw about how the leviathan Sam and Dean should have posted a video of the two of them fucking that the real Sam and Dean then have to deal with? Because that? Yeah, that.