It wasn't often that Mycroft graced the household of 221B Baker Street. It was even less often the times he had visited on the sole purpose of talking to his brother, the house unoccupied by another soul.

"No." Sherlock glared at his brother, violin bow in hand. Mycroft sighed in annoyance, resting his weight onto the ever-present umbrella.

"Persistent as always brother dear, and despite my great distain in asking for your assistance-"
"There's always the option of doing it yourself Mycroft. We both know you're more than capable." The elder Holmes laughed once.

"Unlike you, some of us have duties that require our attention more." Sherlock scoffed, lowering his violin and sweeping past his brother into the kitchen, dressing gown billowing behind him. He waited for a reply, fingers drumming impatiently on the handle of his umbrella.

"Sherlock. Stop playing with your chemistry set and help your brother. This feud is becoming unnecessary."

"When was this ever necessary Mycroft?" He paused, almost lost for words, causing a smirk to appear on his younger brother's lips. "You were the one who felt the need to flaunt your intellect just to rouse my anger, need I remind you?" Sherlock, despite showing his mental capabilities far more than required, had always been jealous of Mycroft, the quiet genius, always having more power and control than he let on.
"Ah yes, but it wasn't like you didn't deserve to be shown up in front of Mummy. She was awfully disappointed when you blew up your first school lab at the age of 11." Mycroft tutted at the memory, lowering himself to the sofa and gazing around the flat, his nose wrinkled in disgust at the décor. Sherlock stormed back into the room, anger rolling off him in electric waves.

"Leave. Now." He spat, glaring holes into the side of his brother's head.

"Oh dear Sherlock, I thought Mummy had brought you up with better manners than that. That's no way to treat a guest, let alone your brother." He flashed a crooked grin at the younger Holmes, taking pleasure from eliciting a reaction.

"I hate you." Sherlock stated simply, the snide comment making him use all his willpower to not strangle the man on the sofa. No-one ever made him this furious, except when he was alone with his brother. John acted as a catalyst, allowing him to challenge his emotions with less dangerous methods. Mycroft chuckled.

"Your emotions always did bring out the stupid in you." He chimed, eyes fixed on his umbrella. Sherlock lost it, lunging and yanking his brother to his feet by his tie, slamming him against the wall. He saw the flicker of fear in Mycroft's face, only for a split second and he grinned, almost deliriously high with the impulses rushing through his mind. Mycroft was always so calm and collected, a stony exterior, and Sherlock wanted to break it down, piece by piece. He wanted to wipe that insolent smirk from his brother's face after so many years of trying. He yanked on the tie, pulling Mycroft's face inches from his. There it was, the emotion behind the mask again. They were pressed flush to each other, Mycroft caged between Sherlock's free arm and the wall.

"Never call me an idiot, brother-mine." Mycroft felt his younger brother's breath hot against his cheek, the sensation making him swallow a lump in his throat, resisting the need to close his eyes, keeping the hard, cold composure.

"I was taught never to lie. I tend to anyway, but I thought I'd make an exception in your case" His breath hitched, as he was quickly rewarded with Sherlock's knee, jutting sharply between his thighs. Pain coursed through him momentarily, gritting his teeth in an attempt to suppress the feeling of want swiftly following it. He kept his brother's gaze, praying that he wouldn't catch the slight dilation of his pupils.

He had no such luck.

Sherlock shifted closer to his brother, lips millimetres from his. Mycroft's eyes darkened again, Sherlock hiding the smirk that threatened to show.

"It would seem, dear Mycroft, your body betrays you." Sherlock murmured huskily, the elder Holmes giving an audible gulp at his words, both hands pressed against the wall, trying to back away uselessly.

"Stop… Sherlock…" The younger man gave a low chuckle.

"We both know that's not what you want…" He ghosted his lips against Mycroft's. "And not what's going to happen." His mouth pressed firmer to his older brother's, his fingers looping around his tie, jerking it to force the man closer to him. Mycroft gasped at the fabric digging into his neck, feeling Sherlock's tongue delve into his mouth at the desired effect, coaxing him into the kiss. He brought both hands around to his brother's shoulder to push him away. This was wrong, and he was enjoying it far too much for his own good, his trousers already beginning to feel tight.

"Sher…" He mumbled uselessly against his brother's lips, the expert tongue darting around his mouth silencing all and any words. A moan escaped him as Sherlock's knee slipping higher up his thighs, rubbing against the bulge in his trousers. The younger brother grinned against his lips, Mycroft beginning to respond to the kiss, fighting for dominance with his tongue. Sherlock refused him it, the hand that was on the wall coming around to un-tuck his brother's shirt; deft finger's quickly making work of the buttons on his waistcoat after. Mycroft's hand half-heartedly attempted to bat his fingers away before fisting it in his brothers dressing gown when the attempt failed, the other tangling in his curls. Sherlock's lips left the elder Holmes', instead latching onto his neck, sucking long and hard to leave a red mark. Despite how this had begun as a way to unhinge his brother, Sherlock was slowly losing control over his own body, rutting against Mycroft's thigh to relieve his aching hard-on. The older brother was somewhat shocked to feel the arousal against his leg, not thinking Sherlock capable of such a thing, but looking at their current predicament, he could see why.

"I'm going to take you, right here against this wall brother-mine, I sincerely hope you don't mind." Sherlock muttered, his baritone lower than usual, in Mycroft's ear, sending shivers down the politician's spine, his erection becoming painfully hard within its confines.

"As long as you know what you're doing my dear" Mycroft groaned out, as Sherlock's fingers turned to his shirt, exposing his chest then his stomach.

"I know enough to make you scream my name." He lost it. Mycroft crashed his lips against his brothers, taking the opportunity of shock to force the dressing gown to the floor before Sherlock regained his composure, hands pressed against the now bare chest of his brother to slam him back against the wall. Mycroft growled, a low, unnatural, feral sound, before pouncing on the shirt of the other man, ripping it open, buttons pinging across the flat. Sherlock, both impressed and annoyed scowled momentarily before lavishing his brother's neck again, sinking his teeth into his pulse point as punishment for ruining his shirt.

Mycroft whimpered in pain and want, pressing his arousal into Sherlock's now still knee, fingers raking down his well sculpted chest, leaving angry red trails in their path. The younger Holmes hissed, capturing his brother's lips with his own, kissing him with a hunger he had never before shown, fingers dancing down the light smattering of hair on Mycroft's chest, a thumb swiping over his left nipple, eliciting a dark moan of pleasure from the other man. His hands continued, long fingers making quick work of the belt at the end of their journey, discarding it randomly behind him.

Sherlock pulled away slightly as his forefingers curled around the loops on his brother's trousers. Mycroft's hair was slightly tousled, his lips, swollen, parted, irregular pants coming from between them. Heavy lidded eyes, black with lust, watching every movement the consulting detective made. He traced the red marks on the older man's neck with his tongue, sliding his trousers from his hips with ease. Mycroft's erection was more prominent with just the fabric of his boxers covering them, and Sherlock swore he could see it twitching through them. The offending clothing soon joined the rest on the floor, leaving the politician in his jacket, waistcoat and shirt still, his chest heaving in the visible space between them, his dark blue tie resting just above his pulsing erection.

The detective stepped back to pull off to discard the rest of his clothes quickly, Mycroft quickly catching on and doing the same. Sherlock's hand grabbed his when he reached for his tie.

"No. Leave it." He commanded, pressing against his brother again, taking the tie in hand, tugging the other mans head down to kiss him, grinding their now naked bodies together, both making unheard of sounds of pleasure at the feeling of their two lengths pressed together, creating delicious friction. Sherlock grabbed his brother's hip, hooking the leg around his waist, pressing his member to his entrance. Mycroft looked at him in horror.

"No, Sherlo-" He screamed mid-sentence, Sherlock plunging into him in one fell swoop. The older brother almost keeled over, pain shooting up his body at the lack of preparation. Sherlock face contorted into a malicious grin, the politician completely at his mercy. He inched out, Mycroft shaking and babbling incoherently, both hands digging into his brother's shoulders for support. The detective pulled out completely before slamming back in, burying to the hilt, Mycroft hitting the wall with a crack. He groaned, his senses overwhelmed with pain and pleasure, his heel burying into Sherlock's lower back, fingers sinking below his collar. This rhythm continued for a while until Mycroft became adjusted to the size of Sherlock, gasping and panting for more, using his hand to fist his shaft in time with his brother's hips. Sherlock grabbed Mycroft's leg again, angling his thrusts to hit his prostate, each touch sending the older brother closer and closer to the edge.

"Sher… Sherlock…!" He managed to cry out, spasming as his climax hit, spurting his seed over both himself and the other man. Feeling his brother tense around him, Sherlock's orgasm followed quickly, burying himself deep into his brother, emptying his load.

They both stayed entangled like that for a few minutes, slowly waiting for their breath to come back.
"We should…"

"Yes. I agree" Sherlock pulled back from his brother, turning to search for his clothes.

"Sherlock, I got the shopping you asked for…" John froze as he opened the door to the flat, spotting the two naked men, his eyes almost popping out of his skull.

"What the fuck did I miss this time?"

A/N: GUESS WHAT GUYS. I REGRET NOTHING.
Seriously. I ship Holmes!cest so hard it hurts. So forgive me.
Also, I've roleplayed smut but never written it properly, so tell me how I did. Help me improve biches, I want all the sexuals.

Also, I am Mark Gatiss and I will kill again.

I joke.

Or do I...