[A/N: Warning for brief asphyxiation and some blood and knifeplay]

"So, what are you after?" Dean asked. He hadn't been with Sam in years and he wanted to know exactly what he was expecting. Not to mention... he wouldn't mind hearing him ask for it. Judging by the lack of fresh scars, bruises and cuts his brother had, he hadn't shared much with Jessica.

"Just... Dean you know what I want."

"So nothing's changed?"

"...No."

Dean walked towards him, taking the knife from him carefully, his arm slipping around his waist. The blade was sharp and Dean didn't want to make any cuts he didn't mean to. Besides the fact that it was best to keep them in places that people couldn't see (they'd learned that early on), Dean was methodical, even if he didn't look it. He liked his actions to mean something and Sam had always been the same. If you just went cutting and hurting wildly, everything lost meaning.

Dean ran the tip of the knife slowly up Sam's body, watching the fabric of his tshirt hitch up. When the knife reached the bare patch of skin revealed by the v-shaped neckline, Sam shuddered, a low moan coming from him as Dean pressed the edge of the blade against his neck.

"So, are you going to get this shirt off or am I going to have to cut it off of you?" Another moan and Sam was wrapping his arms around his waist, tugging at the bottom of hist tshirt. As he pulled it off over his head, Dean almost sighed. He could pretend all he wanted about there being nothing special about his brother but, damn, he was gorgeous. He watched as Sam's eyes dropped to the knife, his hand running through his hair and Dean though he looked a little like a puppy. A rabid puppy: all snarl and dark eyes. He couldn't remember when his little brother had turned into this, into some passionate, sinister, fucking delicious version of himself but he'd always hidden it well. To everyone else, he looked tame, harmless, but it took one flash of cold metal, one touch in the right place and he came undone and Dean had always loved it.

"Dean, I-"

"Shut up. Get on the bed."

Dean raised his eyebrow when Sam went to speak again and he stopped, his mouth hanging open for a second before he scrambled backwards, getting onto the bed. Like Dean knew he would. He remembered that Sam had always had a problem with authority, except when it came to him, when it came to situations like this. It was one of their things. One of the many things they shared, mirrored perfectly. Dean never really knew if it was a coincidence, or if Sam had just picked up on what he liked, or vice-versa.

He climbed onto the bed, pulling Sam's knees apart, moving between them. He was hard already. Dean felt him thrust his hips upwards, seeking friction. He trailed the knife over him again, pressing hard enough to make Sam shudder, almost hard enough to break the skin.

"Please, Dean..." Sam whimpered.

"Shut up, or you get nothing."

Sam's lips pressed together tightly and Dean smirked.

"Good."

He ran the knife up to Sam's collarbones and made a shallow cut, watching the blood slowly beading at the surface. He only gave the smallest whimper when Dean ran his tongue over the incision; Sam was biting his lip, trying to keep all of his noises in. Dean's cock was throbbing now, the towel barely covering anything as he sucked hungrily at Sam's clavicle. He let him thrust against him; he should stop him, he really should but the sensation was too good.

Sam bucked his hips and started to grind hard against him as Dean dragged the knife along him again, making another cut below the last, deeper this time. The blood flowed freely and he pressed his lips against Sam's skin. He was grinding harder now and Dean almost forgot when he was doing. His brother's breathing told him he had to put a stop to this or it'd be over very quickly.

"Sam, stop it."

A sound escaped his brother, half groan, half whimper, but he stopped moving. Dean shifted his hips, moving up his body slightly so he could kiss him, and Dean knew that Sam could taste his own blood as he bit he lips. He bit harder and Sam's hips twitched beneath him, a desperate moan vibrating against his mouth.

"What is it, Sammy?" A small twitch of annoyance, Sam thought that Sammy made him sound like a child. "Tell me what you want."

Sam just stared up at him, his pupils dilated, his lips tightly closed.

"You can speak."

"I- Dean, I need..." he paused. Dean smirked, Sam always had a problem asking for this. He could fight, he could hunt, he could snap someone's neck at a moment's notice but he always got awkward when he needed to come.

"Come on, Sammy. I know you need it. Tell me you want it, tell me you're still my little slut."

Dean pressed the tip of the knife against Sam's ribs and he felt him shudder, his hips bucking again.

"Speak."

"I need to come, Dean. Please."

It must have been a while since he'd gotten any. Well, no, he probably got plenty from that girlfriend of his, but not how he needed it. Not like this. Dean hadn't even touched him yet, this was all from the knife, the blood. From a little friction and pain. That was all it had taken for him to come undone.

"Not yet. Me first."

Dean moved away, sat back between his brother's legs, pulling him up with him. Sam sat before him, his blood running in rivulets down his chest, seeping into his jeans. He was staring at Dean's hard cock, his lips moist with his own blood.

"Come on then, slut."

He didn't need to ask twice. Sam's head was between his legs before he could blink and Dean dug his fingers into his back as his mouth sunk down on his cock. He ran his hands over his skin and came to a stop when he felt the small bumps of the scars. He traced the D with his fingertips, remembering when it had been new, when the blood had still been flowing. It had been their second time with the knife and Sam had begged him to do it. He'd thought it was too sentimental, stupid, but it sure did feel good claiming him as his own. He picked up the knife from the bed and ohfuckthatthingwithhistongue.

"Nghh, do that again," Dean said, lacing the fingers of his empty hand in his brother's hair, pulling hard. Sam's moan vibrated through him and he felt like he might just come already. He traced the knife over the scar and he felt Sam's shoulders tense, readying himself. As the tip reopened the old wound that had been cut into him many times, Sam swallowed, sinking lower on Dean's cock. His tongue flicked again, sending jolts right up Dean's spine and he had to urge himself to hold it, he had to finish his work. He ran the knife around the letter, rounding the incision. As the end of the curve joined up with the first cut, completing the letter, Sam flicked his tongue again and that was it, he was done. Dean held Sam's head down as he came, dropping the knife and pressing his now empty hand onto the fresh wound.

When he released him, Sam was gasping, his back searing, his lungs empty. Dean grinned at him and raised his hand to his mouth, holding it out for Sam to lick, cleaning his blood off.

"You always were a good cocksucker, weren't you?"

Sam only nodded, still breathing heavily. As he sat back, Dean saw that his cock was straining against his stained jeans. His crotch was wet with blood and precome and Dean knew that if this was with anyone else, Sam would have been tugging them off desperately. Now, though, now he was just waiting, his eyes pleading. Dean reached out and ran his fingers lightly over the bulge in his jeans and the noise Sam made was positively obscene.

"If you have anything to say, speak up."

"Please... fuck, Dean, please, I can't-" Another groan, louder this time as Dean squeezed his cock through the wet fabric. "Please."

Dean unbuttoned his jeans for him, sliding them down as he pulled his hips up to help him. He wasn't surprised to see that Sam wasn't wearing underwear; he'd probably only expected to be allowed to rub up against him and underwear only lessened the sensations. Faint red patches of sticky blood had seeped through the denim and Dean wanted to lean forwards and lick at them but he wasn't giving him that much. Not today.

The way Sam bit his lip as Dean wrapped his fingers around his cock told him it wouldn't matter. He wasn't going to have to do much. He squeezed, much too softly and began to stroke gently, slowly. The pleading sounds he was making were beautiful and Dean couldn't help but smile. He ran his other hand along his collarbone, his finger trailing around Sam's neck. Time to see if Sam still shared something else that they used to. He squeezed, gently at first, his pressure increasing as his fingers locked around his brother's throat. Not too hard, just enough to constrict his airflow, enough for Sam to feel the blood pounding in his head. His hips jerked wildly and Dean knew he hadn't changed at all.

Dean could take full credit for this one. He'd had a bit of a thing for strangulation, the way the soft skin felt under his hands, the way he could feel the pulse, the ragged breaths being pulled, the way he could hold someone still by pressing the right spots. He'd thought about it, he'd thought about the fact that he'd walked in on his father throttling someone and he'd linked it together. It wasn't a big deal, it was hardly the worst thing he'd picked up from his father. He remembered the time he'd asked Sammy to let him choke him, just for a bit. Sort of asked. He never truly asked his brother for anything. Of course, he'd loved it. He loved anything he knew he shouldn't. They were careful, though and as Dean saw Sam's eyes begin to roll, he loosened his grip.

Sam's hips were thrusting harder and Dean just let him, savouring the sight of him, covered in blood and thrashing for him. It didn't last long. A few more thrusts and Sam was positively panting, small moans and words escaping him. Words like please and fuck and Dean. Dean squeezed harder again and then Sam was coming, shuddering and gasping for breath as he was released from his brother's grip.

"Fuck, remind me why I left again?" he said when he'd finally recovered the ability to speak.

Dean just smirked. It was good to have his brother back.