Title: Teaching Sherlock A Lesson

Author: starjenni

Disclaimer: Sherlock and John aren't mine! Mainly because of the restraining order.

Pairings: Established Sherlock/John.

Warnings: Men kissing men, men kissing women, hellava lot of kissing really. Oh and swearing.

Rating: T

Spoilers: All of them.

Summary: John gets jealous. Sherlock doesn't. Yeah right.

John wouldn't say he was a particularly jealous man per se, no more than the next man anyway, and with some things that others felt envy over at he felt no envy at all. Such as Sherlock's ability to deduce anything about anyone, he thought - it was amazing, it was quite incredible and he admired it, but, unlike a lot of other people it seemed, he wasn't envious of it, he didn't want it, he was perfectly happy to enjoy the privilege of watching Sherlock do it all instead.

But this lack of otherwise widespread envy in some areas didn't mean he didn't get jealous at all, especially when, for instance, the before mentioned Sherlock (his month-long boyfriend - urgh, he still couldn't quite say the word - boyfriend, boyfriend, it sounded weird) had just spent over an hour and a half chatting the same girl up in the pub they were in.

It was for a case. Of course, of course it was. Sherlock didn't do women. Sherlock barely did people, it was a daily astonishment to John that he was with him at all. So it was for a case that he was chatting so, and smirking so, and flirting so…but that didn't make it any less…annoying.

He downed the last of his pint, grunted "Another" to the barman and pretended to ignore the high pitched giggling of the girl as Sherlock came out with another of his thinly disguised innuendos (and just where the hell did he get them from? John wondered. Was there a list somewhere in 221b, full of carefully planned out and memorised sex jokes?). He ground his teeth together slowly and decided on ten more minutes. If Sherlock didn't have his information after that then it was just too bad, because any more than ten minutes of this and John was going to smash a glass over someone's head.

He turned back to the teasing and flirtatious couple in the booth and very almost dropped his drink altogether.

He was kissing her. Sherlock Holmes - Sherlock bloody Holmes - was leaning over, all dark coat and dark intent, and had his sodding tongue down her sodding throat.

And he was apparently doing a good job of it too, because the girl was moaning like she'd just seen a SALE sign in New Look.

John thumped his pint back down on the bar, just as Sherlock's phone went off and he pulled away from her, all charm and smiles, with lips made red by her lipstick.

John tightened his fingers around his glass. Sherlock looked at his phone, made all the visible signs of looking suddenly worried (another act, of course), said a few more murmured words to the slut - girl, and then got out of the booth and walked up to John.

"We have to leave quickly," he whispered in John's ear, on the pretence of paying for his drink, apparently completely unaware of John's thunderous expression, and then off he swept, like an overdramatic vampire, the girl's dreamy gaze following him all the way out.

John gave it two minutes, then left as well.

He stepped out into the freezing street, to see that Sherlock had already hailed a cab.

"Come on," shouted Sherlock, waving at John.

John turned right, stuffed his hands into his coat pocket and stormed off down the road instead.

He heard a brief, "What are you doing?" and then a more insistent, "John" but ignored both. There may have been other cries of confusion, but his blood was pounding in his ears so loudly that everything else was drowned out, and he only knew Sherlock had caught him up when a hand grabbed his shoulder and made him slow down.

"What are you doing?" Sherlock said, matching John's fast pace effortlessly with his ridiculously long legs. "I've got to get back to Scotland Yard - Lestrade - "

"Go ahead then," John said - no, have to be fair about this, snarled. "I'm not stopping you."

"What - where are you going?"

"Baker Street."

"But that's the other side of the city."

"Yes. Well done."

"John." This time Sherlock's hand on the shoulder stopped John fully, right in the middle of the street. John sighed and whirled around to face him; he was looking utterly bemused.

"I don't understand," he said, with genuine concern. "What have I done?"

John's jealousy rapidly did a u-turn and drove straight into pure, holy rage. "What have you done?" he snapped. "What have you done? You don't even realise what you've done!"

"No - I - "

"Sherlock, you just snogged the face off some girl! In front of me!"

Sherlock blinked. The traffic lessened momentarily, making the world abruptly quiet and surreal. "And?" he said.

John threw his hands up in the air, and turned to leave again, but Sherlock grabbed his shoulder with the other hand as well, swivelling him around properly.

"It was just for a case," he said. "You know that."

"Certainly didn't look like it," John sniped, trapped now into arguing face to face. "Looked more like you were taking full advantage of the situation, if you get my drift."

Sherlock's mouth went very thin, a bad sign, and he let go of John's shoulders. "I told you I thought she might be in cahoots with Maddox and his gang, I was attempting to discern if this was true."

"By giving her mouth-to-mouth?"

"By ensuring that she had been smoking the same cigarettes Maddox smokes. She wore a nicotine patch, but I could smell smoke on her breath. Why would she smoke if she was giving up then, unless it was in a social situation, one she couldn't get out of in case she looked rude? Maddox smokes a very rare and particular type of tobacco, but I couldn't decipher it by smell alone, so I decided that I needed to taste it. Plus kissing her gave me the chance to take her phone." He waved it at John. "This should tell us just what Maddox is planning next."

John crossed his arms. Sherlock hesitated a little awkwardly and pocketed the phone again. "So there. It was for a case. It's fine."

John stared at him. "Sherlock, it is not fine. Even if it was for a case, that's not the point."

"I don't see why - you knew there was no meaning behind it, so logically - "

"Sherlock, I wasn't exactly thinking in logical terms!"

The look Sherlock gave him was the sort of blank look John got every time he tried to make some topical reference or talk about celebrities that were household names everywhere else apart from, apparently, 221b.

He sighed and uncrossed his arms. "Okay, look at it like this. What if you saw me kissing a girl - how would you feel?"

Sherlock shook his head. "That's different."

"Really? How?"

"For me there is only you."

John faltered briefly, hesitated. "Sorry, I'm not getting this."

Sherlock sighed. "You have had other relationships. Men, women. There have other people whom you have liked, desired and loved before me. Statistically speaking, there are most probably other people in the world who are perfect for you and you for them. In other words, there are others for you. But for me, John, there has been no one but you. I am certain that I have never felt any desire, sexual or otherwise, for anyone but you and I am equally as certain that I never will. If you died, or left me, I would not move on to anyone else, not because I would not want to but because there wouldn't be anyone. John, there is no one in the world for me but you. Therefore, if I saw you kissing someone else, there would be a chance that this person was another person for you. With me, you can be sure that is not the case. So it's different."

John was vaguely aware that he was staring at Sherlock with his mouth open.

Sherlock sniffed and shifted uncomfortably. "So," he said, "If we could carry on - "

"What if I was doing it for a case?" John interrupted. "Or for some other reason - for a reason that you knew had absolutely nothing to do with any desire or liking for the person? Would it be different then?"

"Of course not."

"Really? You wouldn't feel the slightest bit annoyed?"

"If I knew your motives behind it were not fuelled by desire, then of course not. That would be the only logical action to take."

"I'm not talking about logic, Sherlock, I'm talking about jealousy."

"I only ever act in a logical way."

Sherlock said it completely straight-faced, completely sincere, but John snorted anyway. "Right. Sure."

He glanced down the road, to another pub which a gaggle of partying girls were just entering, and an idea came to his mind. "Right," he said, a little more cheerfully. "We'll see about that."

They entered the pub, stuffed to the brim with girls in pink clothes and silly hats that read 18 Today - Watch Out! in sparkly silver letters. John grinned and led the way to the bar.

"Let me get this straight," Sherlock said, turning his nose up at the girls. "You are going to kiss someone, some random girl, just to see how I'll react."

John winked at him. "Absolutely."

"That's ridiculous, John. I will not act any differently than I have said."

"We'll see." John got to the front of the bar and smiled at the group of the girls. "Is it your birthday then?" he asked the closest one. She giggled drunkenly and shook her head, and there was a small scuffle as the birthday girl (complete with tiara, blonde bunches and drink-glazed eyes) was shoved to the front.

"Gimme a birthday kiss?" she slurred, batting fake eyelashes at him.

The girls around her screamed and squealed. John grinned, said, "Certainly," in his most gentlemanly voice, and then leaned down and kissed her on her lipgloss-sticky lips.

Beside him, Sherlock did nothing.

Right, thought John and ramped it up a bit, opening her mouth under his, taking hold of the back of her head and giving her what he was sure was probably the best snog of her young life. She clung to him rather tightly, which confirmed it, and the whoops of the girls turned into screams of glee.

But Sherlock still hadn't moved.

Maybe he had been right after all, John thought, feeling the pull of disappointment low in his stomach. Maybe it really didn't matter to him. Maybe it was all logic, logic, logic.

He pulled away from the girl, feeling let down, and she stared at him for about half a second, her cheeks bright pink, squeaked something and then disappeared back into the pink and silver crowd surrounding her.

John - his lips covered in that disgusting sticky stuff - turned with a sigh back to Sherlock.

And froze.

Sherlock's face was a picture. A dark, brooding, furious, utterly jealous picture. If people could be dead just from wishing it, John was pretty sure all the girls would be lying cold and stiff by now - Sherlock's eyes were practically screaming bloody murder.

John felt his face break into a grin. "Ah ha," he said, which was when Sherlock grabbed him by the coat and hauled him back outside.

The street was empty, but apparently not empty enough for Sherlock's frame of mind, because he immediately shoved John into a nearby alley.

John turned back around to him, still grinning because he didn't know how to stop and said, "I told yo - mmph!"

The 'mmph' was because his mouth, which had just been losing the previous sensation of having a tongue in it, was once more assailed by the same sensation, though a complete different one this time. This was Sherlock's tongue, and it, like the rest of the kiss, was hot, heavy and determined. This was a demanding, furious, invasive kiss, this was the sort of kiss that made the rest of the world dissolve into a white-hot, burning, completely unimportant mess. This was the sort of kiss that took everything, shook it up, and shoved it to one side, because it was nothing compared to this, absolutely nothing mattered, not where he was, not who he was, nothing, nothing except this.

When it stopped, possibly years later, John realised he was backed up against the cold and rather damp alley wall, and that he had his hands fisted in the lapels of Sherlock's coat, and that the man himself was at the moment sucking insistently on his bottom lip.

John mumbled something, then pulled his lip out of Sherlock's mouth, the man's teeth nicking the underside of it slightly. "What are you doing?" he asked.

"Erasing the taste of her," Sherlock snarled, and ran the tip of his tongue harshly along John's top lip.

John didn't know whether to laugh or sigh. "I think you've managed it." His entire mouth tasted of Sherlock - that strange, acidic, electric, sharp taste that was Sherlock all over, like the smell of pines, like biting into snow.

Sherlock attempted to turn his attention back to John's bottom lip, but John pushed him away. "If this is what happens when you get jealous, I've got to try it more often," he murmured, and Sherlock surged forward and kissed him again, a bitey, rough kiss in place of a bitey, rough comeback. John succumbed to it gladly, but stopped Sherlock's hands when they started wandering south, because he was getting too old to be shagging in alleyways, plus he had some standards.

He shoved Sherlock away again. "Home," he demanded, or tried to.

Sherlock glowered. "This is all your fault," he said. "Trying to teach me lessons."

John smiled, warmth spreading through him like sun under his clothes, and kissed Sherlock briefly, all sweetness and light. "Home," he repeated, adding, "And you deserved it."

Sherlock sniffed but said nothing.

They went home.