John's concentration was waning; the novel that he was holding loosely in his hands had been on his "to read" list for nearly six months now, and he had only just gotten the chance to begin reading it. Confined to his bedroom in the flat because of Sherlock working on a particularly toxic experiment, he had needed to find something to occupy his time. He didn't have anything new to update on his blog – that was partly the reason why Sherlock was doing more extreme experiments, as he was bored – he wasn't tired enough to take a nap, and he didn't have any work files to update; he had free reign to do whatever he wished. The book had been conveniently placed on the edge of his desk, so he had picked it up and sat in the armchair in the corner of his room. For a while he read attentively, finishing the first chapter in under quarter of an hour – but the further he read, the less interesting the book became. John forced himself to keep reading, otherwise absolute boredom would set in and he would find himself increasingly annoyed at Sherlock for deciding to do an experiment like this now…

There was a large part of John that was intrigued by Sherlock's scientific capacity; put aside his observations and deductions – the level of intricacy that Sherlock's brain worked at was phenomenal, and fascinating. The connectivity that occurred when Sherlock was trying to make an experiment work, his self-correction as he went along, would take most scientists days to figure out, but Sherlock seemed to naturally understand how chemicals interacted. John appreciated now, why Mycroft believed that being a 'consulting detective' was a waste of Sherlock's abilities; if he had gone into research he could have found cures for illnesses, or been working upon the regeneration of stems cells – he could have gone far! But Sherlock had no particular interest in using his scientific prowess in that manner – he could submerge himself in the world of experimentation, but only when it was for his amusement, otherwise he just wasn't interested… But John could hardly complain about that – if Sherlock wasn't a detective, then his own life would be a lot more monotonous; living with Sherlock brought a spark, a flash of lightning illuminating the world at large with him at the epicentre.

John's grip on the book had slackened further, and it had slipped onto his knees with his fingers only lightly brushing the paper of the pages. For the past few minutes he had been aware of a slight, but not uncomfortable, pressure in his lower abdomen; but as he looked down at his lap the cause of this pressure became clear, the visible lump he could feel pressing against his left leg. It had been years since the last time he had spontaneously gotten an erection… He must have been a teenager the last time it had happened without warning or arousal, but the steady warmth of pressure and gentle tingling, rather like the beginning of pins and needles, that was spreading from his abdomen, into his balls and along the length of his penis made it undeniable. For a few seconds, John retightened his grip on his book and brought it closer up under his face, attempting to ignore the warm feeling that was beginning to pulse through him; but it was no use. Why should he ignore it? He was a single man – he reminded himself. Placing the book open on the arm of his chair, he shuffled in his chair to obtain a more comfortable position and unzipped his jeans. The second his hand made contact with his hard penis, a shiver shot up his spine; his fingers were cold as he wrapped them tightly around the base of his cock. Stroking up and down slowly, John closed his eyes and rested his head back against his armchair, exhaling rather erratically – this felt so good!

"John! JOHN!" A flurry of noise suddenly came from the closed door of John's bedroom and Sherlock burst unexpectedly into the room with an ecstatic look on his face. John's heart had leapt into his mouth, being caught short – jerking off – was horrifying! Luckily, John's hands seemed to react quicker than his brain – grabbing the novel which had been open on the arm of his chair and slamming it quickly onto his lap, covering up his uncovered erection.

"Don't you ever knock?!" John yelped in surprise, the words left his mouth very fiercely; his heart was still beating very fast and he could feel his face turning red in utter embarrassment, the rhythmic throbbing of his penis wasn't fading either… He just wanted Sherlock to leave him alone so he could finish; clearly he had been frustrated for a while, the level of ecstasy coursing through him was only one reason why this felt so good. Sherlock didn't seem to have noticed the cause of John's extreme reaction; he was standing in the doorway, with a set of protective glasses over his face, a test tube clutched in his hand and a blank look on his face. John didn't usually react in anger whenever he appeared like this… Sherlock surveyed John in the armchair, pink cheeked, one hand clutching onto the arm of his chair and a book turned upside down in his lap. "God Sherlock, this is my room! It'd be nice to have a little privacy!"

"Oh… sorry." Sherlock muttered, looking rather confused at this. "I'll leave you alone, sorry." Sherlock withdrew from the room, closing the door behind him; and for a few seconds, John listened carefully for footsteps drawing away from the room which would notify him that it was safe to carry on.

Throwing the book aside impatiently, John closed his eyes and grabbed his cock a little less carefully this time – his movements were jerky, impatient; it was in line with the level of warmth that was pooling in his abdomen. He could hear himself taking rattling breaths, sucking in air and expelling it so fast that he knew he was being louder than was necessary. But fuck, who cared? He was sex deprived and horny – he should do this more often! Pleasure was flooding through him as he squeezed and stroked at his penis; his whole body was reacting now, shaking in anticipation.

Shifting forwards in his chair, so he would have easier access to the full length of his cock, he opened his eyes just a fraction – and stopped abruptly. Standing in the doorway, with a small smirk playing across his features, was Sherlock…

"FUCKING HELL!" John exclaimed, there was no way of hiding what he was doing now; how dare Sherlock think that it was alright to snoop on him like this?! Desperately trying to cover up his genitals with his hand John stared at Sherlock in disbelief, shaking his head. "I knew you were insensitive Sherlock, but seriously?!" Annoyance and anger were mingling in with the arousal that he could feel in his heart, but also throbbing in his penis. Sherlock didn't looked abashed, or embarrassed; on the contrary, he tilted his head to one side, as though interested in what he was observing. "You don't just stand and watch another guy jerking off!" John shouted, beginning to try and shove his penis back inside his trousers, but Sherlock spoke quietly and calmly.

"Don't…" He said quietly.

"Don't what?!" John snapped, feeling very disgruntled that he had been interrupted for a second time, and that Sherlock had stood and watched him masturbating as though that was normal!

"Let me make it up to you." Sherlock replied cryptically; John was still annoyed at Sherlock, and he wasn't in the mood for Sherlock's stupid games. Sherlock, however, had taken several steps forwards until he was right in front of John's chair; John's heart was pounding and confusion was beginning to marr the discomfort of the unfinished orgasm that he had been working up to. What was Sherlock doing? Keeping eye contact with John, Sherlock knelt down very slowly – reaching out his hand and placing it on top of John's right hand, which was gripping onto the arm of the chair.

"Sherlock – what are you?" John didn't get the answer out fully; Sherlock's free hand had gently unhooked John's from covering his cock. Very slowly and tenderly, Sherlock's fingers had wrapped around the base of John's penis. For a few seconds Sherlock just stared into John's eyes – it was as though he was asking for permission, but John had felt a rush that he hadn't expected; he gave the smallest of nods with his head and bit his lip as Sherlock's thin fingers began to stroke up his erection. "Sherlock, I…" John started, cold shivers encasing all of his body as Sherlock's fingers were touching the most intimate part of his body; but the end of his sentence turned into an involuntary moan. Without warning, Sherlock had taken John's penis fully into his mouth – the warmth and wetness of Sherlock's mouth caused an eruption of sensation in John. "Oh god… god Sherlock!"

He hadn't expected this – he had felt angry when Sherlock was standing watching him; but now, with Sherlock's tongue running up the shaft of his penis, as he sucked at the tip – he felt spectacular… Sherlock's lips rubbed sensuously across the head of John's cock, and the tingling sensation redoubled in John as he felt the brush of Sherlock's tongue… His whole body was shaking, he knew he wasn't going to last much longer – not with the preparation he had given himself, before Sherlock had started sucking him off, but he was in too much bliss to conjoin coherent sentences – all he could get out was: "Sherlock – I… I can't…" The pressure in his abdomen released before he could warn Sherlock, and he came hard.

Panting heavily, and leaning exhausted, in his armchair, John opened his eyes after a few seconds… Sherlock was still on his knees – one hand caressing the inside of John's thigh, and a peculiar smile on his face.

"Sherlock… I…" John stammered, out of breath.

"I've wanted to do that for a long time." It was remarkable how calm Sherlock's voice was; John suddenly remembered that Mycroft seemed to think Sherlock would be alarmed by sexual acts… If this was Sherlock alarmed, how utterly amazing would he be when he was comfortable?! "Are you alright John?" Sherlock was acting as though nothing had just happened – as though he hadn't just given his best friend a blowjob.

"I… Christ Sherlock! That was amazing!" John exclaimed honestly, shaking his head disbelievingly and staring into his friend's eyes; he knew his cheeks were flushing red again – had Sherlock just said he had wanted to do that for a long time?

"I'm glad you enjoyed it!" Sherlock smirked, and John felt an odd leaping, fluttering sensation in his heart. Sherlock had just given him a blow job – that wasn't something that "just friends" did for one another… was he? Could he be hinting at something?

Acting upon impulse, John leant forwards and his lips met Sherlock's; their kiss was soft and gentle, John felt Sherlock's tongue brush his teeth and a shiver of excitement chased up his spine. Sherlock's hand had reached up to John's face, cupping his chin; and John's hand had buried into Sherlock's hair. Surely this meant something… When John pulled away he kept his face close to Sherlock's – eyes interlocked intensely.

"Does this mean what I think it does?" He whispered quietly, hoping to hear the reply that he suddenly was desperate for.

"What do you think it means?" Sherlock asked, his fingers stroking the side of John's face.

"That I'm not imagining that this is more than just a friendship… that this means something…" John expanded, and the small smirk on Sherlock's face widened into a smile.

"I think…" He spoke slowly, deliberately, and tantalisingly. "This is definitely more than just a friendship."

For a moment the two men just looked at one another, drinking in the sight of each other – both experiencing happiness, a joy that they both had been longing for, but had been too scared to express to the other. John broke this moment, with a playful smile crossing his features: "Is it my turn to return the favour?"

"Oh god, yes…"

A/N: I hope you've enjoyed reading this! (I know I'm not very good at writing smut, but I'd love to know what you think anyway!)