Posted originally on the Archive_of_Our_Own at https://archiveofourown.org/ works/11368854. Rating: Explicit Archive Warning: Underage Fandom: Supernatural Relationship: Dean_Winchester/Sam_Winchester Additional Tags: ageswap, Daddy_Issues, Dean_is_fourteen_Sam_is_eighteen, really_fucked up, blowjob, Dubiously_Consensual_Blow_Jobs, Extremely_Dubious_Consent, Daddy_Kink Stats: Published: 2017-07-02 Words: 1625 ****** Brain ****** by whatthefrickfrackpaddywack Summary The tension in the air feels thick enough to smother him, mollases pouring into his lungs, sweet baby boy freckles pink and flushed and still covered in baby fat, oh my god, oh my god- This is Sam's fault. (Ageswap, where Sam is the big brother and Dean finds a way to keep him from running away to Standford.) Notes I might continue this, might not. Let me know in the comments!! (Love y'all!) Sam can't breath. "What the fuck are you doing," He whispers. Hands gripping the seat cusions on either side of him, sleep leaving his body in a jerking instant the second he looks down. Dean doesn't say anything. Baby brother eyes looking up, caught, ticking teeth terrified. Dean's hands are shaking where they grip his dick. Silence. The tension in the air feels thick enough to smother him, mollases pouring into his lungs, sweet baby boy freckles pink and flushed and still covered in baby fat, oh my god, oh my god- This is Sam's fault. He should've hidden the papers better, should've got home earlier, should've lied and said "No, I'm holding this for a friend, why would I ever leave you?" But he'd stood there. Frozen in the doorway as Dean looked up from the acceptance letter in his bone white grip. Standford. "Sam, what is this?" Betrayal. That's what it was. "Did I... did I do something wrong?" No, no, baby you didn't do a thing.  His hands have lost their soft, grown rougher, calloused. They know their way around a needle, can reload a gun in the blink of an eye; they shake where they're gripping the scholarship information. "Please don't go." "De..." "Please, please, Sammy don't go-" Tough as nails baby brother, crying in the middle of the moldy bedroom floor. Sam rocks him back and forth, back and forth, here comes the train. Choo choo. Sam ran his hands through dirty blonde hair, wracking little sobs, "Don't go don't go," gripping the front of his shirt like a lifeline, like a noose. "I-I'll stop s-stealing all the good cereal, I-I can do y-your half if the chores, I can change Sammy-" "It's not you, Dean, it's me, it's not your fault..." He smooths big hands over a fourteen year old back. Growing bigger and bigger every day at the same pace as Sam, who keeps shooting up with growing pains and awkward limbs and shaggy teenage hair. He still fits in his lap perfectly. It would be so easy. "It's me. It's all on me." I'm a fucking pedophile. "S-sammy please." Bammy, Sammy, Daddy, John. Daddy daddy daddy- "Don't leave me." "My bus leaves tomorrow." nonononononono Dean had punched him in the face, screamed, cried, hit him over and over till he realized Sam wasn't fighting back wasn't offering a punch. Just kept holding him, holding him, take your brother outside and run as fast as you can. Holding his baby. Dean screamed a savage "Fuck you!" Ran outside and slammed the door. Dean's hair looks wet, a leaf sitting sideways on the top. There's mud on his elbows, AC-DC T-shirt soaked through. Sam doesn't have to look up to realize it's raining outside. Dean swallows. Opens his mouth. Closes it. He must've snuck in while Sam was asleep, saw him sitting on the couch. Must've slunk down between Sam's too long legs, knelt on scraped scabbed boy knees, kiss it better Sammy, on the musty carpet. The fucking blinds are open. Sam exhales shakily, can't tear his eyes away from Dean's hands on his fucking dick, from the thing he'd fantasized over and over till his cock was raw and his eyes stopped crying, till the water in the shower ran cold, legs pulled up to his chest on the bathtub floor. Dean looks away, down at his trembling hands. "I...I want-" "No." Dean flinches back, eyes blinking rapidly. Face scrunches up in that way it always does right before he's gonna cry. "You can't leave me." Jesus fuck how did he not wake up. Dean licks his lips. Leans down slightly. Sam's entire body tenses up, flinches back. Dean looks like he's been shot. "Why the hell do you think this is gonna convince me to stay?" His voice sounds raw. Like he's been screaming for hours, screaming through the streets for Dean, Dean baby where are you? "I... I hear you sometimes. When you think I'm alseep." No. Nononononono. "I thought I was dreaming, the first couple times. But then I started hearing you in the... the shower-" Dean gulps; Now that he's started talking, it's like he can't stop. "I thought I'd done something wrong, but I didn't know what it was till...till I started getting it up listening to you." His tiny hands squeeze on Sam's dick, feels like those hands are on his throat. "I-its my fault, it's what I do to people, should a stopped sitn' on your lap or something, just what I do to people. It's not just you, it's the grocery clerk a-and some of Dad's friends, it's me, I did this-" Sam's choking. "Dean, no-" "I've been tryna wrap my mind around it every free second I get, keep panicking when I tried ta think about it. Thought it was a misunderstanding, 'cause you never touched me like that before, stopped touchin' me fuckn' years ago just, thought maybe I was goin' crazy-" "Stop it." "No!" Petulant little brother. Winy little brother. Chubby baby brother between his legs. "No, no, Sammy you gotta stay, I'll do anything, I know that this is my fault, gotta show you that it's okay..." He lowers his head down, and Sam feels the first puff of sweet breath over the head. He slaps him. Hard. Dean looks shocked, blinking, breath coming in deep and quick. If anybody ever hits you, you tell me. I'll rip their fucking lungs out. His head turns slowly back around, red hot fury blossoming in his cheeks. His eyes look murderous. In one quick motion, he takes Sam down to the root. "Fuck," Sam's panicking, oh, he's panicking, hands coming back up around Deans head to rip him off but they're shaking too badly to do much more than cradle as his baby brother chokes. He cant be doing this right, doesn't feel like he's doing it right, but Sam still shivers over him, the skin over his hipbones pulling taut under hesitant pressure of Dean's fingertips. It feels strange, terrible, horrible; feels like heaven, like he wants to stay in the concave warmth of Deans throat for fucking ever. This shouldn't be in his mouth, ever. He is this close to pulling out and just running for it, get in that bus and run away from his baby, just as long as this here ends right now, it will be good enough. But then Dean fucking moans. His eyes are looking up, watering slightly, terrified what the fuck is he doing look in candy apple green. It barely fits into his mouth. Sam groans at the sight, its stretched so far, gotta hurt by now, puffy pink lips so kissable, so pretty, feels like he's dying. Girl lips. Cock sucking lips. Baby brother lips. Sam tries not to, oh, he tries not to but he bucks up anyway. Dean gags, fists a hand into the fabric of Sam's t-shirt. Another proof of Sam's hunger, another proof of how rotten Dean can make his brother become - undeniable and violent and scary. This is fucked. This is a crime.Warm and wet and velvety and Sam hates it with all he's worth, hates the sloppy slurping noises, hates the rough rhythm of his own ragged breathing, hates the dry heaves coming up through Deans nose every time he tries and goes down too far, too fast, too young oh my god.Thin layer of skin over bulging flesh that forces little hurt noises from Deans throat from how hard he has to force his jaw open. Sam's panting, panting, has never been this hard in his life and it feels like he's going to die, cant help the blood pulsing south, pulsing into that perfect mouth. He bites back evey word, every endearment he wants to say. No baby boy or De or oh my god, don't stop, oh god. Everything he could say would be disgusting, impossible. Dean's hips jerk forward, confused little sound coming out of his mouth, rain soaked jeans tented hard and proud. The blinds are open. Pretty green eyes tear streaked and adoring, Sammy Bammy Daddy Sam, worshiping the ground his big brother walks on, worshiping the cock that's choking him. Sam can't breathe, dick pulsing, balls drawing up tight, no, no, don't do it, he can't come back from this if he does it- Dean has that hatred back in his eyes, fury and murder and things too old for someone so young, so young, little baby boy. He pushes down farther, doesn't break Sam's gaze. "Dean, baby, s-stop, I'm gonna-" Dean's left eye twitches. Pulls Sam's huge hands back down into silky soft hair, doesn't move when Sam desperately tries to push him off by the shoulder. Sam comes with a long, drawn out groan. Everything he's ever wanted, everything he never thought he'd get. Dean sputters. Tries to swallow it, gags so hard he pops off. Coughs into Sam's shirt with cum leaking out of his mouth. Sam's crying when Dean crawls up onto his lap, baby boy tounge forcing into way into a non responsive mouth. He tastes himself. He tastes Dean. He wants to kill himself. "Don't you dare fucking leave me," Dean growls, hips pumping furiously forward, teenage dick standing up hard in his jeans. Sam groans and starts kissing back, biting, touching, Dean. "You can't leave me. I'll find you, I'll fucking find you anywhere, you can't leave me." Sam gets his hand (finallyfinallyfinally) around Dean, pumps once, twice, flicks his thumb around the head.  Dean makes sweetheart noises, girl noises, wines and sighs and squeezes his eyes shut like he's in pain because he is. Sam licks the noises out of his mouth. Please drop_by_the_archive_and_comment to let the author know if you enjoyed their work!