Disclaimer: I don't own either Harry Potter nor Sherlock, obviously. Also, this has teen boys having detailed wet dreams/mind sex (you'll see what I mean). With each other. If it offends you, please turn back. Flames will be used to barbecue lamb ribs.

Make your dreams true

John Watson was a mystery. Which meant, of course, that Sherlock Holmes, Ravenclaw to his marrow, was dead set on solving him – and also found him deeply fascinating, but never mind that. He would never admit it – he didn't need any more teasing than he received already. What with his fascination with some branches of muggle studies and their possible application to potion brewing. The idea that non-magical people could have something to teach wizards, and better their techniques, was simply anathema for most people in Hogwarts, not just snotty Slytherin first years.

Which brought him right back to John – honestly, the Gryffindor was an obsession, and had been for six years by now. Sherlock's pet project – the one that attracted so much scorn to him – was a direct result of his friend's culture shock during first year. One would imagine that at first impact, the blond would be incapable of wrapping his mind around the existence of magic, dragons, and other assorted creatures. Muggleborns often were.

But – always unique – John seemed more stunned by their curriculum and frankly appalled at all the subjects he insisted were lacking in it. How was he supposed to have a life when he got out of here? He wanted to become a doctor, and this was missing Physics, Biology, and Chemistry at least, if he was supposed to be stuck here until he was 17. "No, it's not Alchemy, Lock, it's the advanced version of it, and what do you mean they might not offer an Alchemy class at all if it's not popular enough?"

His friend had mellowed out some after discovering that he could eventually become a magical healer, studying its own special curriculum. But being told that the muggles had an 'advanced' version of one of their subjects was enough to make knowledge-hungry Sherlock insist that John acquire a book for him at his next holiday. "You simply have to help me! I promise you can pick my appearance while we're experimenting with that. I'll even do that one Hufflepuff girl you keep staring at…"

Because of course Sherlock was weird even by wizard standards. Not that he cared – being a metamorphmagus was mostly useful for when he needed to conduct an experiment he knew would raise some eyebrows, in the hope of shifting the blame. He'd started at home, with Mycroft – in fact, that was the first, instinctual use of his magical talent – and continuing here had never been something he'd even questioned. Let's just say that the teachers were becoming very apt at spotting people acting out of character, and would never dole out punishment without giving the accused a chance to produce an alibi. Still, if Sherlock was in someone else's skin, nine times out of ten nobody realised.

That one pesky time wasn't Mycroft (their age difference at least meant that he didn't have to suffer his sibling's presence at school too, as he was now bothering people at the ministry with his presence), nor a particularly eagle eyed professor. Nope. John Watson, muggleborn, who gaped at simple things like Lumos "because I've always read into the night and mum would complain about the electric bill and that it was unfair for the environment, and now I can shut her up about both of those." No matter how perfect Sherlock's rendition of someone's appearance was, or how much he changed his usual appearance John could pick him out of a crowd if asked to.

At first, the Ravenclaw had suspected his friend was an untrained legilimens, and recognised him by his mind. After all, some people were naturals at potions, some at herbology, a handful at divination…Legilimency was certainly a useful skill for a child to develop, especially if their family life was less than splendid and they wanted to pick up any angry thought almost before it formed, so they could make themselves scarce. A number of experiments with a thankfully very amenable John (and some less than complacent schoolmates as a control group for John's ability, besides his Sherlock radar) proved that no, the Gryffindor wasn't an instinctual mind-reader. Really, John's improper terminology was starting to affect him too – it was awful.

John, of course, refused to share his secret – no matter how much he was cajoled, bribed or tricked. Besides, it was so ridiculous that Sherlock would certainly be disappointed once he knew – and take care to control himself around him, which would be a pity. As far as the Gryffindor knew, it happened only when his friend caught his gaze, and it was such a fleeting thing that, unless people were staring at him that very second, it was no wonder John was the only one to know.

Sherlock's metamorphism acted up whenever John was around. One of his curls, to be precise. Why that one, laying just under his left ear, he would never know. As soon as their eyes met, The Curl would flash to a deep violet – and take its natural coil back – if Sherlock's style (or cover) of the day required straight hair – for a fraction of a second before going back to normal…or the normal of the moment, at least.

The oblivious Ravenclaw's investigation (and wasn't that an oxymoron, especially when the Ravenclaw in question was Sherlock Holmes) managed to teach John some legilimency on the side though, which was brilliant. You couldn't check if someone knew something if they had no idea what you were talking about, and Sherlock himself had pestered Mycroft – who was an expert in the subject – long enough to pick up some guidelines.

John had assumed his best friend used the technique on a regular basis, given his tendency to blurt out supposed secrets, especially when he wanted something from someone – or wanted to get back at arseholes. But the Ravenclaw sniffed, offended by the idea that such a refined technique would be necessary to read the idiots who surrounded them, and described in detail the science of deduction. No magic at all needed, which was a good idea in case you needed an edge on people and didn't want to bother with flashy duels or waste power. It was no surprise that Mycroft – Slytherin to his core – was the source even for this manipulative technique, though he insisted that the resulting information shouldn't be shared but kept for blackmail purposes.

The Gryffindor, despite being smart in his own right, didn't take to deduction that well, which Sherlock secretly – and guiltily – loved, because as long as his inferences weren't painfully obvious to him, unlike his brother, John would continue to heap praise on him. And his friend's praise should count as an addictive substance. The Ravenclaw was tacitly terrified of the day his best (okay, let's be honest, only) friend wouldn't be in awe of him anymore, which fuelled some of his crazier experiments.

Not that he should have worried. The first time John had entered his friend's mind, after instinctively following his detailed description of what he had to be doing already, according to Sherlock, he was completely stunned. Sure, normal people talked about falling in love with someone's mind rather than their body. But no one else in John's immediate experience had to deal with someone whose appearance changed at whim, or had such an…intimate (what other adjective could one use?) knowledge of a person's mind.

The (literal!) mind palace was part Hogwarts, part – John assumed – Sherlock's home (well, mansion seemed more correct) – part Flourish and Blotts, and some…well, frankly he couldn't even imagine, and even if they were having a literal telepathic communication it still felt awkward and prying to ask. Yes, John realised these were probably silly muggle inhibitions, but he couldn't help how he felt.

Frankly, the first time it happened, John expected to be booted out immediately, but Sherlock didn't seem to mind. Sure, there were locked doors here and there, but his friend seemed proud to show off his inner workings. Honestly, he had every right to be – if Gaudì met Merlin, the resulting building would be undoubtedly less fascinating. And if John happened to do it again sometimes, his friend again didn't protest – secretly hoping to sway him, so that they could become Aurors together instead of John being stuck in a hospital where, magical or not, Sherlock suspected the Gryffindor would be bored to tears in no time. That was the reason the Accident happened…

Since Sherlock liked company when reordering his mind palace lately, and he'd also taken to asking John's input about what to keep, what to discard, and some pieces of décor, John didn't think anything – coming to visit his friend and finding him with his eyes closed – of slipping in to see what the genius was up to. He didn't expect Sherlock to be actually napping for once, all his mental defences down – much less to find himself in the midst of a heated dream starring himself and Sherlock in the Room of Requirements (so that any whim could be instantaneously satisfied…clever, that). The other boy didn't seem fazed at all by the appearance of a second John, and just beckoned him closer with a languid arm. The Gryffindor, though blushing brilliantly – unlike his dream counterpart – was powerless to resist the invite, nor did he want to.

He'd had similar dreams often enough. (Not that he had confessed it to anyone). John didn't even realise he'd shoved aside his lookalike and taken his place, kissing Sherlock senseless – he wasn't even sure if this was still all a mental exercise or if it bled through into reality. At least, judging from the way (dream?) Sherlock's hair flashed through all the colours of the rainbow, and some the blond boy had no idea even existed, he was enjoying himself. The Ravenclaw's hands roamed over him, his stand-in sending him a smouldering gaze and a wink – which really was more like Sherlock's attempts at charming people the muggle way – before joining in again, kissing and touching the genius' nape and back.

John was stupidly, illogically jealous of…himself…But when the boy shuddered and gasped between the two of them, his body shifting slightly to accommodate them better, get more contact, more pleasure, more John, all animosity disappeared. He could only time himself to work in tandem at his best, pet and nip, pinch and lick, kiss and stroke.

The Room of Requirements actually provided when he decided to sweeten the moment, given Sherlock's partiality for honey, by having some to spread on his lover's bird-like clavicles...before licking it off him. He'd never be sure whose idea it actually had been – picking cues was what Legilimency was about, after all, but the resulting moans definitely weren't complaints.

Both Johns trailed lower and lower, one writhing Sherlock between them, clothes disappearing in the very useful way things do in dreams. Finally – after a second or five hours, no one would be able to say – one was nuzzling and licking the boy's sweaty back and curls, while rubbing his member against the top of his thighs, and the other – after tasting a flat stomach – went back to proper kissing, while letting his own cock grind against Sherlock's.

Both boys jolted back to reality, the sticky proof that the mind was the most powerful sex organ in their underwear. Thank God that the Holmes family's frankly indecent wealth ensured that Sherlock didn't have to share either a room or a bathroom (en suite, really?) with anyone else, and his – to understate – opinionated personality ensured that no one else but John would just pop in.

The metamorphmagus' iridescent eyes (a sure sign that he wasn't sure how to feel) opened slowly, and he blushed a brilliant crimson. "Oh God! You're…here…" he breathed.

"Why? Do you regularly dream of multiple me's seducing you?" John asked, winking.

"I…you…you don't just…" Sherlock stammered.

"Look, sorry but – you didn't seem to mind. And, what you might have missed while we were…busy… was that I didn't mind at all. It wasn't because it was your dream, or something. So, if you're up for it, you know…what about we become proper boyfriends? You know, outside our brains? Not that I didn't love this, but –" the Gryffindor rambled, a hand rubbing his nape.

"Boyfriends?" the boy's voice was uncharacteristically squeaky.

"Or not. I mean, I get it, some people turn you on but you don't want to have anything to –" John replied, looking somewhere above the other's left shoulder.

That made Sherlock jump, a hand clutching his friend's arm. "No! I mean yes! Yes yes yes! Boyfriends would be great, amazing, wonderful." He was copying John's style, wasn't he? Then again, the Gryffindor could be utterly oblivious sometimes.

John chuckled. "Perfect."

The Ravenclaw nodded. Damn. He knew that he'd missed the right adjective. But his brain didn't want to work at full capacity right now.

"What about I actually kiss you now, and then maybe I can use boyfriend's privileges to ensure that we conserve water by showering together?" Never let it be said that John Watson wasn't daring.

"Would a single yes suffice?" Sherlock shot back.

The answer didn't come in words.