To my readers: Although he won't show up for a while, for timeline purposes you can think of this story as beginning a few months before Harry starts Hogwarts. This is primarily the tale of Sherlock and John's friendship. Reviews are welcome.

(Warning: reviews contain spoilers)

If Sherlock Holmes could read his military service in his leg and his sister's drinking habits in his mobile phone, John had very little doubt that the detective had also deduced his real secret. Probably from the moment they met. But Sherlock, most uncharacteristically, hadn't said a word.

John was rather grateful.

It was uncharacteristic of them both, actually, that at first they rarely mentioned the magic. Its casual use was scattered around the flat and seldom suppressed, which was the primary reason D.I. Lestrade's drugs busts were so annoying. Fortunately, Sherlock's reputation was such that when Donovan discovered the dish of half-dissected Horklumps soaking in Shrinking Solution, she merely rolled her eyes and put it back in the microwave with the now-congealing jar of eyeballs.

Judging by the way the tea seemed to have made itself that first morning—John had slept in after a wild night of kidnappings and gunpowder and chasing cabs all over London—and every morning since, John guessed that Mrs. Hudson was no stranger to magic either. When he thanked her, however, she simply gave the standard sweet smile and "You're welcome, dear," before continuing down the hall to berate Sherlock about the state of the flat.

The constantly catastrophic state of 221B was the one thing that magic couldn't seem to fix. It was an implosion of papers and microscope lenses and old potion bottles. It wasn't all bad. The sink did clear itself of dirty dishes every few days (Mrs. Hudson again, John suspected; one day he would catch her at it). Stacks of books straightened themselves periodically, and the wallpaper seemed mysteriously immune to even Sherlock's most exothermic experiments, but for the most part the inhabitants of 221B existed in a limbo of half-organized chaos. John quickly learned to deal with it, military habits notwithstanding. Something about their flat was delightfully reminiscent of the old common room, the corner by the fire in which he and James and Peter and Sirius had often huddled, usually with a stolen bottle of butterbeer or two, to plan out the next week's adventures…

Not thinking about James and Peter, John reminded himself for the thousandth time. And, Definitely not thinking about Sirius.

James and Peter. Merlin, he missed them.

John hated himself when he caught himself missing Sirius too.

In many ways, however, Sherlock was an acceptable substitute. He was more than that, of course…but sometimes John caught himself mid-laugh and found himself wondering whether his brilliant flatmate hadn't been there all the time, dragging the rest of them along to steal Potions ingredients and somehow transforming snide remarks about Severus' hair into verbal monuments to the god of wit.

Sherlock had caught John gazing at him strangely, once or twice, when these reminiscent moods took him. But he never mentioned it.

When mugs of potion began turning up on the coffee table, without fail, each night of the week before the full moon, John didn't mention that either. For some reason it didn't bother him that Sherlock knew—either because it was already unthinkable that he wouldn't, or because, bizarrely, John trusted Sherlock, or because Sherlock knew everyone's secrets about everything, and next to that turning into a bloodthirsty monster once a month didn't seem quite so embarrassing. John was grateful, too. Potions had always been his worst subject—there were all sorts of rules about temperature and timing and stirring motion that he'd simply never had the patience for. For a potion so enormously complex, John knew even Lily's coaching wouldn't have been enough. Not that he had that option anymore.

Additionally, long-term unemployment in the Wizarding world had shrunk John's Gringott's account to the point that he'd more than once considered closing it entirely. Wolfsbane, if made correctly, cost upwards of forty Galleons a bottle.

Yes, John was ridiculously grateful.

Once or twice he almost voiced it, but something held him back—perhaps the silence that was its own sort of communication between the two of them, or perhaps the nagging realization that this was Sherlock's own way of showing gratitude. For the night with the cabbie, maybe. For everything that had happened since.

A lot had happened. It had taken John much longer than he'd admit to come to terms with Muggle technology (what was wrong with a good old-fashioned owl, for heaven's sake?) but when he'd typed the first reluctant words into the empty cyberspace of his blog, he couldn't have imagined how quickly it would fill with stories. Him and Sherlock and their completely mental adventures. Some of them, to his mind, even madder than roaming the Forbidden Forest in the dead of night with what looked like half an escaped menagerie.

That, he cringed, had been an insane thing to do.

"You invaded Afghanistan."

The voice wove into John's thoughts, making him jump when he realized it had spoken aloud. Sherlock glanced up from his petri dish and smirked.

"Just a reminder."

"I hate it when you do that," John growled, rubbing at his forehead with the sleeve of his jumper. "I swear, Sherlock, if I wasn't convinced you thought Legilimency was boring…"

"Enlighten me, John, what could be more boring than poking around your small, uninventive brain?"

"Don't pretend you can't do it, you twat."

Sherlock's hand stilled with the micropipette raised over the petri dish.

"I can," he admitted, so quietly John barely heard him.

"Right," said John, too triumphant to register the pause. "So, how do you expect me to believe…"

"You've spent the last five minutes gazing blankly at the screen of your laptop, which is currently opened to your blog, if your painfully sluggish typing earlier was anything to go by. That you were thinking about the latest case is an obvious assumption, but your left hand trembled briefly, as though recalling the unrelenting tedium of your life before I came along…"

"Hey," said John, mildly indignant. Sherlock steamrolled on.

"…seconds later, your hand curled into a fist and you smiled, but your eyes remained unfocused. Clearly a stroll down memory lane. Recalling what? The ceasing tremor in your hand indicates calm, lack of anxiety. You were remembering a time you felt at home. In this case, both your latent inability to function without adrenaline, and certain, if you'll pardon the description, wolfish qualities about the smile…"

"Sherlock."

"…would indicate an adventure of some sort. Presumably involving myself or friends from your younger days. You've been staring at your blog, but without any hint of recognition, and although earlier you glanced at me periodically, you haven't done so within the past three minutes. Not one of our cases, then. The memory was enjoyable, but you cringed just now, so probably something from your school days, when you were younger and more stu—that is, prone to acts of recklessness. I was just reminding you that whatever your youthful folly, you've certainly done more insane things since…like invade Afghanistan."

John stared at Sherlock for a moment, then tossed back the last of his tea, emerging with a small smile.

"I'm never going to get used to you, am I?"

"Prior experience would forecast the negative," murmured Sherlock as he turned back to his dish of bacteria, but John could have sworn he caught the hint of a smile on his face too.

It remained a point of fact that at their first meeting, John had assumed Sherlock was using Legilimency. Sherlock still found that amusing, although he had to admit it was a twisted (if poorly applied) example of his own favorite axiom: When you have eliminated the impossible, whatever remains, however improbable, must be the truth. When confronted with Sherlock's deductive prowess, most Muggles either theorized that Sherlock was stalking them, or jumped directly to 'impossible'. John, by assuming otherwise, had shown his hand as a fellow magic-user. As though it weren't already painfully obvious.

He hadn't said anything at that first meeting. Not in front of Stamford. But (even more than curiosity) Sherlock had been counting on misplaced irritation at the supposed mental invasion to bring John to Baker Street the next evening. He was not disappointed. Although, with first Mrs. Hudson and then Lestrade twittering about, they had no real opportunity for conversation until the cab ride.

"About yesterday," John said, hunching into his jacket. "Don't ever do that again."

"Do what?" inquired Sherlock innocently.

John shot a look at the cabbie, who appeared reassuringly exhausted after a long day, and more or less deaf to what was being said behind him. "You know what."

"Pray enlighten me, Doctor."

"There," John snapped. "That. It's incredibly rude, not to mention downright wrong. The flat's nice, I'll grant you that, but if I'm going to have to learn bloody Occlumency just to keep my thoughts to myself, the answer's no."

Sherlock studied his potential flatmate. It would seem the doctor was even more sensitive to intrusions of privacy than he had judged. No real surprise there, of course, not considering…but it could pose a problem. Haircut, posture, mobile phone clearly well-used, though handled with an unfamiliar distaste…Sherlock could hardly help it that the data leapt out at him.

Sensing the moment to make a few concessions, the taller man drew his wand from his coat and tapped it casually against his knee.

"For someone so queen-and-country, you're proving remarkably cavalier about the Statute of Secrecy." Sherlock dropped his voice. "I wasn't using Legilimency." An unfamiliar smile tugged at the corners of his mouth as John raised his eyebrows and lowered them again in disbelief.

"Prove it."

And Sherlock did. So thoroughly that John had trusted, ever since, that what appeared to be mind-reading consisted, quite simply, of startling deductive leaps. It was the truth—perhaps the only certainty where his new flatmate was concerned—and a major reason that Sherlock took a malicious pleasure in smiling into the faces of police sergeants while invective like 'Freak' flew over his head. Sherlock Holmes would use magic for everything else, but never The Work.

The only times John's faith in this tenet wavered were when Sherlock read his mind without magic. It wasn't difficult, or even particularly interesting, for the detective to trace the thoughts flitting in their predictable pattern across his flatmate's face. But it had piqued a degree of curiosity about John's past, just enough that Sherlock had looked into it. Not using Legilimency.

John, too, carried memories he didn't talk about.

More words came, in the months that followed. More talk about…well, life. Magic.

After a few months it had become ridiculous, at least in John's mind, that he knew hardly anything about the man sitting across from him. Well, he knew him, Sherlock Holmes, his face and his moods and his preference for coffee, black, two sugars please. But he didn't know a thing about his past, didn't even think he'd heard the name 'Holmes' spoken in Wizarding Britain, which was odd as it tended to be a close-knit community. Muggle-born, perhaps: that would explain Sherlock's love of science. Or maybe a foreign family, though his polished public-school accent and Mycroft's excessive government involvement seemed to indicate otherwise.

Now John thought about it, there had always been something familiar about his flatmate. Destiny, thought John, grinning, if nothing more explicable. Probably just seen him at Hogwarts once or twice…

"Stop thinking about me," floated Sherlock's voice from the sofa.

John cursed. "Stop doing that!"

"You're thinking. It's obvious. It's annoying. Also probably wrong. What do you want to know?"

"What makes you think I want to know anything?"

Sherlock stretched and rolled onto his side, eyes still closed. "Okay, you don't want to know anything."

John groaned and stalked to his armchair. There was a long pause in which Sherlock did a very good job of pretending to doze off, and John wasn't fooled.

"It's still true, you know, what I said that first day," he finally exhaled. "We've been chasing around these crime scenes for at least two months, tracking down murderers, bank robbers, Merlin knows what else…and we still don't know a thing about each other."

Sherlock raised one eyebrow and John amended, "Okay, I don't know a thing about you."

"Absurd. You know many things about me. My address, for instance."

John chucked a cushion at his head. He hated it when Sherlock was deliberately obtuse. It was simply wrong, a point of disturbance in the set way of things, rather as though Albus Dumbledore had come to him for Transfiguration help.

There was a slight "oof" as the cushion hit its mark and fell limply off Sherlock's face onto the floor. Sherlock heaved a sigh and levered himself unwillingly into a sitting position. Probably, John thought, so that his sarcasm wouldn't ricochet off the ceiling and hit anyone. "Is this your way of requesting the intimate details of my dark and mysterious past?" The baritone voice was laden with irony.

"What—no, nothing like that," said John hastily, recalling that memorable first night when they'd entered the flat to find it swarming with Scotland Yard's finest impromptu drug squad. "That's your business. I'm just curious about…well, a few things really. It's odd to be sharing a flat and not even know the most basic…" Sherlock's stare made John suddenly aware that he was rambling. "Like…where did you go to school?" he finished lamely.

Sherlock pushed himself up on one elbow, looking deeply disappointed. "Same place as you," he said scornfully. "Obvious, John…"

"All right, all right, I was just making sure!" defended John, throwing his hands in the air. "I mean, I guessed that, all right, only Hogwarts has hundreds of students, and obviously we weren't in the same year…"

"Two years apart," Sherlock stated, lapsing back onto the protesting cushions as though already bored with the conversation.

"Okay. I don't think we ever met. Shame, really," said John.

"Mmm."

Well. Acquiescence would have been too much to ask for.

"You're a Ravenclaw, obviously."

Sherlock let out a snort and rolled over. "That's what everyone thinks. Except the bloody Sorting Hat," he mumbled into the cushion.

"So you're not…?" John shook his head, trying to reconcile this information with Sherlock's frankly terrifying intellect. Not to mention his usual attire: a blue scarf and long black coat that billowed around his youthful frame and irresistibly brought to mind images of school robes and house colors. "Then…"

"Slytherin, if you must know. Really John, I hardly think Hogwarts' particular brand of labeling is relevant here..."

"All right, all right, it's not as though I care!" John interjected, wondering what he had possibly said to make Sherlock so touchy. He paused. "Explains why we never met, anyway. I'm sure you've deduced me already, or d'you remember seeing me at Hogwarts…"

He paused when Sherlock said nothing. "Do you remember me?"

There was silence. Then:

"No."

Sherlock made no further effort to break the silence, which elongated until John gave up, heading into the kitchen to make tea. It wasn't much, he thought, shaking his head as he set a mug (two sugars) on the coffee table next to his flatmate, who had drifted into his own thoughts again and didn't seem to notice. Hardly a conversation. But it was a start.

A/N: Sherlock reading John's mind is totally ACD canon, for those of you who are wondering...