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It’s a testament to how fucked up Merlin is when the best fuck of his life is his brother.
And by that he doesn’t mean his bros, as in his mates, as in the guys he shoots the shit with at the pub on Friday nights when really he’s aching for a cock in his arse at home. No. He means his brother. Different moms, same dad.
Not that you would know by how Uther acts. Arthur’s the oldest, not illegitimate child and gets treated accordingly.
But Merlin doesn’t mind much, really. Because when Uther turns the overbearing, demanding dick act to eleven on Arthur, well, Arthur gets in a mood. And when Arthur’s in a mood he needs to take it out on someone.
Merlin loves it a lot, being taken out on. By his brother.
Fucked up.
*****
To be fair, it didn’t really start with Uther, though blaming their respective daddy issues for whatever’s going wrong at any given time is what they do. But no, Uther being… Uther, didn’t make them do shit. They did that all on their own.
It started in the kiddy pool.
And that makes it sound creepy as fuck. They weren’t like, boning each other when they were five, Jesus.
It was the summer before uni and they’d fill the kiddy pool with icy water for a shocky contrast to the heated pool. It’d been a great party. The kind with all their mates, lots of food and beer and slutty bathing suits.
They were both in the backyard after everyone had left, pissed and naked from playing strip water polo. Arthur spread his legs and looked down at himself, his shins bumping on Merlin’s.
“Merlin,” he said, whiny. “Merlin, my dick’s fucking cold. Do something, Merlin.”
Merlin finished his beer with a long gulp and threw the can in the pool before picking up a melting ice cube from the water. It hit Arthur right in the forehead.
“I would if I thought I could find it,” he said, laughed when Arthur made a face, outraged and really fucking dumb-looking.
“It’s right there, you twat!”
He looked so sad about it, Merlin had to do something. He petted little-Arthur with a heavy hand, more grope than pet actually, the skin of Arthur’s balls soft on his palm. Little-Arthur got hard real fast and--well.
“Suck on it, Merlin,” Arthur said.
It was funny, so Merlin sucked Arthur’s cock.
He got on his knees in the pool with his bare arse in the air and Arthur hitching his hips up so his dick wouldn’t be underwater.
Arthur slapped his dick on Merlin’s cheek a couple times, laughing about it, saying shit like, “Bet you won’t do it. Bet you won’t. Suck on your brother’s dick, come on. Put your pretty mouth on it.”
Merlin took him quick and deep in his mouth and gave him a good suck and that shut him up as fast as he’d gotten hard. He pressed with his hands on the inside of Arthur’s thighs to spread him wide, while Arthur rested his cold beer on Merlin’s shoulder like a douche.
Merlin’s a good cocksucker if he do say so himself. Something he’d never really told Arthur before but Arthur learned it quick for sure. He wouldn’t have been able to deny it anyway, not with the ah-ah-ah punched out of him every time Merlin went down, then up to twirl his tongue around the fat, red head of his dick. Not with the way he was fucking up into Merlin’s mouth, a tight hand in the muscle of his shoulder, then at the back of his neck to keep him down.
“C’mon, little brother,” Arthur said, breathy on the ‘brother’ as he fucked up one last time, then came down Merlin’s throat, lifting his hips high, pushing so far back he flattened the side of the pool and water spilled out all over the cement. “Cocksucking champ.”
He laughed, pushed his thumb inside Merlin’s mouth beside his softening cock, then patted his cheek. Merlin could have hammered nails with his dick.
He still spit Arthur’s jizz at his face.
*****
It’s a summer thing.
They don’t go to the same unis, mostly see each other at Christmas and during vacations when they’re both back home.
Merlin loves summers. No one fucks him like Arthur fucks him. No one has a cock like his brother’s. Just fat and long enough to get him just right. No one knows exactly how Merlin likes it, either. Believe him, he’s tried. Two semesters is a long time without someone able to make you come untouched. Someone who can hammer your prostate and make you cry for it.
No one knows Merlin like Arthur knows Merlin. And Arthur might not say it, but Merlin knows there’s not person, not a hole he likes to fuck more than Merlin’s. Because no one fucks Arthur like his little brother does, either.
What can he say, it works for them.
Merlin’s three fingers deep, listening to the fight downstairs between Uther and Arthur. It’s been going on for a while. Long enough that Merlin’s mostly teasing himself now, pushing as far as he can go, then pulling out to scratch at his hole with the edge of a nail. It sends sparks up his spine, his leg twitch and he pushes his face harder into the pillow, tries to lift his arse higher. He spreads his legs. He gets ready.
This one’s gonna be good.
And sure enough, not two minutes after he hears the front door slam, Arthur’s in Merlin’s doorway. Merlin could have waited for him in Arthur’s own bedroom--the bed is bigger, softer--but Arthur likes fucking his brother in his childhood bed. Everyone has their little things.
“What did dad want?” Merlin asks, raising himself up so he can put a hand on the wall, arch his back a little, give Arthur a good view of his stuffed, shiny hole. He says it slow, too, deliberate on ‘dad’ because he knows the reminder gets under Arthur’s skin.
“Whatever,” Arthur says, taking his cock out of his slacks as he crosses the room. He pulls Merlin’s fingers out of his arse roughly, with a tight grip on his wrist and Merlin moans. They’re alone, now, so he allows himself to be loud. Slutty. Arthur spits on his hand, wet his dick and pushes in without stopping until he’s balls deep, has Merlin stretched good. The slide is perfect.
“Fits like a fucking glove,” he tells Arthur. They often talk bullshit when they fuck. It’s hot. “Made it all wet for you.”
“You make the family proud, I’m sure. Always ready like a fucking boy scout.”
Arthur fucks Merlin hard and fast just like Merlin knew he would. Enough that Merlin has to get both his hands on the wall so Arthur doesn’t ram him into it. That way, he can push back too, can meet Arthur’s thrusts, and every time he feels the edge of his trousers rub on his arse, the back of his thighs.
That shit will chafe and Merlin will fucking make Arthur put some cream on it later, but right now--right now the friction is so good, with the stretch, the hard pounding he’s getting, that Merlin’s dick drips all over his pillow.
He cups his hand under his dick and catches some of it, sticky on his palm, and as soon as he’s put his hand over his shoulder, Arthur’s mouth is right there, sukcing, licking at his fingers. So fucking hungry for it.
Fuck, but Arthur is pretty like this. Merlin watches him in the mirror on the closet door, sweaty and flushed with hair sticking to his forehead and his mouth stuffed with Merlin’s fingers and taste.
His golden, perfect, older brother.
Heat burns in his stomach, low and heavy and demanding between his legs, and he whines. “Art--Arthur.”
Arthur puts an arm around Merlin’s chest and pulls Merlin back, makes him sit in his lap, sit on his dick. His mouth moves from Merlin’s hand to the back of his neck, and he grinds, hands on Merlin’s hips to keep him there, move them around on his dick in small sharp circles. He comes with a loud grunt and a shiver, filling Merlin up.
Merlin jerks, so hard and sensitive. It always gets to him when Arthur comes in him like that, empties himself inside. He can feel each pulses through his hole and he clenches down on Arthur’s dick reflectively. His cock aches and Arthur knows, wraps his arms around him tight and Merlin just lets his head fall back on his shoulder.
“Come on, Merlin,” he says in his ear, takes Merlin’s cock in his fist while he’s still fucking coming in his arse. “Make a mess.”
Merlin’s been hard for fucking ever, so it doesn’t take much--a twist of Arthur’s hand and a filthy sideways kiss, mostly tongues, spit, and moans. Just the feeling of Arthur leaking out of his arse, and he’s jizzing all over the sheets.
Arthur pumps his dick hard, doesn’t let up until he’s sure that Merlin’s spilled everything.
“Could have been better,” Merlin says, breathy as fuck, lips dragging over Arthur’s cheek. He shakes, orgasm still buzzing under his skin.
Arthur pushes him forward so Merlin lands in the wet spot, and laughs. “Fuck off. You came so hard there’s jizz on the wall.”
Merlin rolls his eyes, shifts on his stomach and gets his knees under him, getting come on his face but not caring. He’s not the only one who loves this and they both fucking know it.
He spreads his arse open where he knows he’s all red and used and still trickling Arthur’s come.
Because no one eats him out like his brother does.
Fucked up.