"So how's the occlumency going, Draco?" Harry asked his secret Slytherin friend in the privacy of a disused classroom some two days after his Gringotts adventure.

They were sitting in the west side of the castle, so the pale afternoon light made faint patterns on the dusty classroom floor, and the small bodies running around the renamed Kettleburn Club – now Hagrid's Creatures Club – were tiny and antlike as they bustled around well below the fifth-floor window. Their tinny voices were occasionally carried up to the room on the breeze.

Today, Crow was on baby-sitting duty, sitting high up over a window's stonework and coincidentally out of Draco's sight to give the illusion of privacy, but keeping an eye on Harry's decision-making nevertheless.

"Did you manage to get Sn—Professor Snape to teach you after all?"

The blond Slytherin half faced Harry, half the window through which pale light fell, snugly sitting about a foot or so in front of the pile of chairs and the wooden desks that were piled up against the wall. He was comfortably lounging on a cushy green armchair that he'd transfigured from one of the chairs, and smirked when he looked up at Harry's question.

The general air of smug pride he affected no longer irritated Harry as it once had.

Malfoy drawled, "I've managed to source lessons, thanks to your persistent nagging. Fortunately for me, my Head of House's assistance was not required, and I have been making the first points of progress these last few weeks since you," his nasal twang grew stronger, "kept on insisting."

Spread out comfortably on his own conjured armchair, this one in a chocolate brown brocade, Harry quirked a brow even as he threw one leg over an armrest. He was particularly proud of the mix of fabric types, the subtle silver embroidery worked through the entire fabric, and the cloud-like curlicues and stitching that had shaped themselves precisely as he had imagined.

He was basking in the warm bliss of everything going well for once. Even the way silver dust motes drifted across the room added to the afternoon's charm.

"Eh? I didn't think occlumency teachers were easy to come by. I certainly n—nevermind. Who's teaching you?"

Draco sniffed delicately. "My mother."

"Huh?" Harry paused. "Oh." Bellatrix Lestrange had taught the boy last time, Harry was pretty sure, and she must have learnt it from somewhere. It wasn't a stretch to assume it was a Black Family thing. "That's absurdly good luck for you. Is she any good then?"

This time, Draco's tone of voice dropped as he straightened huffily in his chair, the uncrinkling cushions undermining his vehemence slightly. "I'll have you know that my mother is Narcissa Malfoy née Black!"

Crow chose that moment to flap his wings and flutter noisily to another perch near the window tops, causing the dusty air to surge distractingly, so Harry didn't get the full experience of seeing a Malfoy righteously indignant. Nevertheless, the Slytherin was his friend, and the thin lines around his pinched mouth suggested that he actually had been offended by Harry's thoughtless question.

"Sorry, please forgive me misspeaking," Harry backtracked immediately, retrieving his leg from its informal resting place and sitting up straight to impress upon Draco his sincerity. "I didn't mean…well, I suppose I did, but only accidentally…It probably is due to my muggle upbringing that I can 'know' certain things without really understanding their significance."

Draco was already shifting back to slump against one of his armrests, the whoosh of his breath releasing audible from where Harry sat opposite.

"I mean, I know the Black family is Ancient and Noble, right? So, er…" Harry went on. "…She has lots of traditional skills?"

"Your muggles came so close," Draco held up his finger and thumb mere millimetres apart, "so close to ruining you, Harry. You are unbelievably lucky I befriended you as I did."

It was with a flush of relief – that he was now learning – and an arrhythmic heartbeat in his chest – how terribly, accidentally rude had he been last timeline!? – that Harry's muscles tensed to focus on what was important right now. Both feelings at once were a little worrying, but he refused to let the embarrassments of last timeline ruin his current, well-deserved glow.

"That's...fair." He nodded. "Your potions advice, the thank you letters, your financial suggestions…they've been life-changing." And they had. "Literally. If I haven't said it enough yet, Draco, thanks. Really."

The pale-faced boy opposite Harry flushed a pleased pink and waved the compliment away with pursed lips. "Yes, yes. But now I've found another gaping hole in your knowledge. What do you think the Noble Houses are, Potter?"

He was Potter again. Oops.

"Uh…Old? And wasn't there something about the pureblood registry or something?" Harry'd genuinely never cared about the Houses that much before, hidebound, prejudiced and inbred as they mostly seemed to be.

"Hrm? Oh, you mean that whole Sacred Twenty-Eight thing?" Curiously, at this point Draco shuffled in his seat, the tiny crinkling noises of his silken cushions revealing more fidgeting to Harry's ears than was first apparent. Suddenly Draco's pale fingers were very busy removing a small scuff from his black school boots. "Very important families. Powerful. With much history, of course. Yes."

"Uh huh?" An eyebrow crept up.

"Obviously, certain families take it very seriously. Um. Some people...discount it, because most of the families of the Twenty-Eight only arrived here with William the Conqueror. The, uh, Malfoy family arrived at this time, for example."

Harry leaned forward. "Eh?"

Draco paused. "Well, we have a long and glorious history back in Normandy and even before that we can trace our roots to Rome, originally; it has always been said that Malfoys showed decisiveness and cunning, even while uprooting the family from their homeland, since each relocation settled the House in a stronger, more long-lasting position."

"Ooh," Harry's old curiosity reared its head and his wand hand twitched towards his mokeskin pouch before he decided not to actually search for a quill. "Would you say that the magical abilities of your ancestors changed or adapted at all as they moved geographically?"

Startled, Draco glanced up at Harry, grey eyes narrowed in confusion. His fidgeting was diverted. "What? No idea. I don't think anyone's read through those diaries for generations! But anyway, the Malfoy family is also in the Book of Parchment, which some scholars seem to prefer as a definite list of Houses."

"…Eh?" Harry blinked and stared at Malfoy as if he'd never seen him before. "I've never heard of this Book of Parchment!"

"Potter," Draco drawled, blond brows angled, his eyes crinkling in amusement. "You've barely heard of anything. But my point is, the Black family has been in Britain since at least the Book of Bronze – an earlier list of Houses," he added, as if he doubted Harry's intelligence, "so my mother's family grimoire is rich in history and knowledge. The older the House, the deeper their knowledge. Obviously."

"Obviously," Harry echoed obediently.

Draco went on. "There's also the Book of Stone, but no one seems to agree which Houses are in that, because it was written before the current family-name conventions and has caused many arguments over the years."

"Parchment, bronze and stone," Harry repeated, planning to research this all in his own time. "Wait. Grimoire?!"

"The Family Grimoire?" Draco rolled his eyes.

Harry didn't get it. "…Yes?"

"The Bloody Big Book of Family Magics?" Harry wasn't imagining the disbelieving tone in Draco's voice this time. "That everyone except the Mu—ggleborns will have inherited from their families?"

"Ah," Harry managed, wracking his now-prodigious memory for anything he may have heard on the topic. "Nope?"

"…Potter," Draco groaned despairingly, the bridge of his nose pinched tightly between a finger and thumb. "How have you even…?" He gave up with a heavy sigh.

Harry shot a startled glance up a Crow, where the black bird was calmly settled above a medieval stone quatrefoil, and back at the blond boy in front of him again.

The room was warming up as the afternoon sun began to sink lower, towards the horizon, and the pale sunlight began to creep up the classroom wall behind them. Absently, Harry inhaled the faint scents of drifting dust and slowly melting snow, but none of this detracted from the vision of Draco doing mental gymnastics opposite him.

After his long moment of spasmodic shock, Draco stirred from his lounging posture to transfigure Harry a parchment and quill, which shot over to impact Harry's chest with all the impatience of an angry Crow. "Take notes. I'll only say this once, and then you'll run off and do your own research. Urgh. How do I even…?"

Harry obediently readied the quill.

Draco stayed flustered. "I can't even…Bloody hell. I had no hope from Weasley, but not even Longbottom has told you about…?"

Harry's head swivelled smoothly on his neck. "…No?"

"Then again," Draco's pained voice continued as if Harry wasn't worth acknowledging right now, "he probably thinks you can Do No Wrong, the way he believes the sun shines out your arse."

"…Thanks, I think?"

Draco paused for a moment, steepling his fingers until his knuckles went white and his frown lines were dark. "If my father ever hears about this frankly heretical summary I am about to give you, he might murder me in my sleep. Take notes, Potter."

"Yes."

"Tell no one."

"Right."

An expression of self-loathing flitted over Draco's face as he began to speak, painfully quickly.

"Family grimoire. Any family of about more than three generations has one. Like a," out of the corner of his eye, Harry saw Draco cringe, "family recipe book, except for magic. Great-grandma Aquila might add something about cooking magic, her husband Adrian adds an adaption for the Jawbind Potion. Their son, Octavius, invents a new use for Billiwig Stingers. His daughter Ursula creates a twist on the salve for burns before she marries out. And obviously, each new generation adds on extra spells for secrecy, for protection, usually linked to the bloodline or their family magic."

Harry knew about that. He'd picked up new family magics himself.

His wrist ached as his quill scribbled loudly and rapidly in the quiet room. Crow's feet clicked lightly on the stone as he shuffled where he rested, but Draco's hurried voice went on.

"After about three generations of these records, where family members might each add in numerous entries, obviously, the book itself begins to become magic. It might change form – I know for certain that the Malfoy Grimoire didn't always look as modern as it does now, and that's all I can say on the matter – because of the spells and because I'm not a bloody traitor," he added snarkily.

"It might become more organised. Some might update the foreign language records to the current vogue of language. Others don't, each family's is different."

Harry's notes grew longer.

"But the whole point of all this is that my mother was born a Black, a Black of the Blood, and had access to Black records which she can still use, even if she is now unable to transmit that sacred family knowledge on."

Harry's green eyes shot up from his scrawled bullet-points. "Hang on, didn't you say—?"

"My mother can teach me the generics of Occlumency, Potter," Draco snapped, "Even if the specific Black specialities are now lost to me because I was born a generation out."

Huh.

He went on. "And with," Harry caught the grimace that flashed over Draco's face and flinched in sympathy, "repeated exposure to her Legilimency, I find that I can learn the basics of the Art without anyone breaking their Vows or needing to marry into another family."

Harry remembered his own days with Snape and wondered if he owed the man a small, very small, apology. Perhaps he truly hadn't been able to give better instructions.

Nah.

They sat in peaceful quiet for a bit, Draco's chest slowly heaving a little less with each breath as he calmed down, Harry turning things over in his mind. The sun passed behind a cloud, and from the Creatures Club below came Hagrid's, instruction for clean-up, and an echoing chorus of agreements.

Hang on a minute…

"Does she know about me?" Harry asked, leaning forward where he sat. "Your mum, I mean, since she's been, um, 'practising' with you?"

Draco froze, then licked his lips in sudden thought. "…Maybe?" There was a moment of tension before he relaxed again, his shoulders sinking back into his armchair. "It doesn't matter if she does though. My mother would never hurt me."

"You do have all the good luck," Harry mused, back on the topic of Occlumency now that he'd been appropriately inducted into the Idiot's Guide to the History of Family Magics. "When I was learning," he paused to choose his words, "I had—was almost desperate enough to go to Sn—Professor Snape for help. My first teacher was all, 'clear your mind, fool' and 'think subtly, you arrogant toerag.' I had to figure heaps out for myself, and it took me bloody ages."

Draco had found from somewhere, or possibly conjured, an iridescent peacock feather and was twirling it around slowly in the afternoon light. His eyes were fixed on it and the curious glimmers of colour and light that shifted as it swirled. "I see. Apology accepted, Potter. You do seem to be the type who needs to know the 'why' of your actions before you understand the 'how'."

Harry twitched and avoided Crow's sudden chattering agreement from above Draco's head. He'd never actually been described that way before, and suddenly a few things seemed to slot into place in his mind.

"Merlin, Draco! That's the nicest thing anyone's said to me all day. But I actually brought the whole thing up to ask if you needed any thoughts from me." Below their window was the distant sound of students chattering cheerfully as they left the Creatures Club, drifting up to their window in fits and starts. "I mean, your mum'll probably know way more than me, but I've started up more recently and might have something to offer?"

Draco rolled amused eyes. "No need to be so worried, Harry. I'm hardly about to bite your head off now you've explained. I'm still at the meditative stage, Mother tells me. Making rapid progress, apparently, soon I won't need the spell-guide at all, but Mother won't say what the next steps are."

"Spell guide?"

"…To help you reach the initial state of calm before you've learned to do it yourself?

Harry bit his lip. "Bet Snape would hate that."

"Well, he's a tad ascetic in his philosophy…But what did you do then?"

"Huh. I had to do it the hard way. Er, on my own."

Draco looked suitably impressed.

Harry paused for a moment of thought and rearranged himself on his comfortable wingback chair. Grunting a teeny bit, he tucked his right ankle under his left knee in a tidy cross-legged pose and plonked a silver cushion over his legs.

"Just...the Blacks do have a reputation for madness, no offence. You do know the mind needs to be 'fluid and flexible', right? So, um, you can't…what was the phrase… 'control and corral your own thoughts inside boxes, fences or foolish constructs', right?"

It was easier to quote from the little handwritten book now than it had been a year ago. Harry's memory really had improved by an order of magnitude.

Draco—who had quite finished working himself up into a paroxysm of intellectual exasperation and was now slowly relaxing, coming down off his high—quirked his head politely. "I beg your pardon?"

Harry shrugged. "Just the one lesson I really want you to remember, from my own experiences. Something your mum's, the Black Grimoire, might not have mentioned? However you choose to organise your mind, don't just box it in, alright? Don't forget that."

Draco frowned thoughtfully. "Harry, I know that despite all evidence you're not actually an idiot, but I don't quite…"

"Just, did your mum say that, just maybe, she'd learned a little but wasn't an expert in it?"

Draco startled. "How did you know?"

"I bet her sister is the one who's really good at it and look at her state of mind. Er, I mean," Harry added hastily, "I assume she's not doing well these days. If we could look, I meant. Not that she was ever a paragon of normality or…whatever."

Draco's raised eyebrow spoke his scepticism loudly.

Harry coughed. "I figure—Sirius hasn't mentioned it to me, but I don't know how much of pre-Azkaban remains in him anyway—I was just wondering if maybe a stiff mental construct was what contributed to the Black madness. When they get far enough into the Art to get good at it, I mean. You need to keep your mind moveable," Harry explained, quill and parchment forgotten as he waved his hands around earnestly. "Keep your organisation and defences flexible. Changeable. However you do it. Because I think that's why the Blacks sometimes go mad."

Crow fluttered down from his high perch in a small explosion of wings and sound, and landed on the back of Harry's chair, nipping gently at the whorls in his hair.

"Tell her what I said," Harry exhorted, raising his hand up to tease at Crow's sensitive neck feathers. "Just, bring it up as something to think about, and then she what she thinks about the whole thing. Then," he spoke over Draco's splutters, "then if you get good enough, I'll let you know what's going on in…a few months, I guess. If even your Mum thinks you've got it down."

They'd chatted a bit until Draco's transfigured chair popped abruptly back into a desk underneath him, and then Malfoy had made his excuses and hobbled off to regain his wounded pride.

Harry, meanwhile stayed comfortably in the darkening room and instead spoke Sirius' name in the little silver hand mirror.

There was a pause, and then rustling. Light and darkness flashed around the silver mirror in Harry's view and then his mirror's pair was apparently pulled from a pocket so Harry could see his godfather lying on…a fancy-looking rug?

"Harry, my boy! Pup! Light of my life!" Sirius barked at him cheerfully. "Frieda says 'hallo', Scheffer beat Baumgartner, Stöber, and Strauß to remain undefeated three duels from the top, and Remus has got a job translating for the Embassy! You flying high, kiddo?"

"Haha, very subtle," Harry grinned at his godfather, whose laugh lines were coming back around his mouth and eyes and whose very proper gentleman's accoutrements gleamed bright and gold in the light from the enchanted lamps that were dotted around the room out of sight. "Did you win money?"

A pleased scoff dismissed the thought.

"Congrats. Personally, I'm flying under the radar at the moment. Done another awesome thing, two awesome things actually, so that feels really good. And obviously school starts tomorrow but I'm nicely ready for it and feel okay about things right now. Who's Frieda?"

"My favourite bartender," Sirius grinned, waggling his eyebrows salaciously. "Her beer is bloody brilliant and she's so quick at the curses that she gives me tingles. But really, how is the flying going?"

He winked roguishly and Harry thought for an instance that he could guess at how Sirius had looked at seventeen.

Harry rolled his eyes. "I'm…the transformation's going so well, I feel like a bloody genius some days, I'm not going to lie. The shift is almost instantaneous now, and the W—My fellow animagi are jealous, hand on heart. Fortunately, I'm kept humble by my literal wings. I, er, I got off the ground the other day."

"Ehhhh!" Sirius exclaimed. "Fabulous news! My little boy's all grown up and into the air, on wing and all. Quick! How do you feel about going by Wren? Robin? Arden? Peregrine? Feathers? How'd the flight go?"

"Crash-landed half a second later," Harry bit out, flushing worse when his godfather roared with laughter. "And I think I only caught that bit of air because I jumped off the couch, anyway. So I still can't flap and I still can't steer. By the way: I've already got a name, thanks. I'm pretty happy with it too."

"Nonsense," Sirius snorted. "It's tradition that you can't name yourself. I'll admit Feathers is a tad too obvious, but Peregrine seems manly enough. Although now that you mention it, I do remember that one time your father refused to be called Horny, so I suppose you do get the right of refusal…"

"For his antlers?" Harry cringed. "I can't believe he stayed friends with you after that."

"Tried to get the name Sugarpuff to work for me instead, actually, and it almost worked too. Fortunately Moony came to save the day. Speaking of which, what about Talon? Remus came up with it, and it's got a good ring to it."

"Actually, the—"

"Or Swifttalon, to match Padfoot?" Sirius added hopefully.

"Ooh, I might have gone for those," Harry shrugged in apology, "if my partners-in-crime hadn't already named me. I'm Crowley, to match Crow, and cause general chaos and confusion, and provide an alibi if needed. I feel it fits somehow."

"Crowley, eh?" Sirius rolled the word around his mouth.

"I'd rather be a trickster than a… 'Talon'," Harry repeated. "Than a weapon, maybe? Though like I said, it's nice. Anyway, Crowley seems settled in me, somehow."

There was a thoughtful pause, during which time Sirius run his tongue around the outside of his teeth and Harry figured out that Sirius was hanging out in his bedroom, some kind of cake-tasting session in observance according to the plates arranged around him on the floor.

Harry could almost taste the heady scent of cream and sugar that must be in the room.

Sirius was the first to speak. "Huh, Crowley then. Your magic's accepted it. That's good. That's important in getting things to settle. Will, wand and word, and all that," Sirius said, resigned but proud and already ricocheting along his new mental pathway. "Does Minnie still teach that?"

"Professor McGonagall!?" Harry's eyebrows shot up. "Yes. I've heard it in most of my classes."

"Jolly good then!" Sirius grinned again. "Merlin but I love that witch. If only I was a few decades older…Want some Bienenstich? Oh, you can't. Never mind then." He picked up a fork from out of Harry's sight and cut out a bite-sized piece which he stuffed in his mouth. "Mhh-mmm." He chewed, then swallowed noisily. "But what did you actually call to talk about?"

"Hrm? Ah! Right!" With a flick of his wand, Harry cast muffliato around himself and conjured up a couple more huge, squashy pillows, in browns and silver silks and cottons, on which to lounge. "Right. Grimoires."

On the rich, green and gold carpet, lamplight glinting in the background behind him, Sirius inhaled sharply. The deep breath caught a piece of Bienenstich, it went down the wrong hole, and Sirius coughed and hacked loudly for a couple of minutes. The mirror tilted left a little, bouncing in time to Sirius' fist punching the floor and Harry's view began jumping worryingly.

Harry's forehead creased more the longer the hacking gasps went on for.

"Wa'er," Sirius gasped between chokes, his face beginning to turn puce and the little veins in his forehead protruded.

With a crack, a half-full crystal glass of liquid appeared right next to his right hand, and Sirius grabbed it and downed it with the desperation of a drowning man.

Something worked, and Sirius soon put himself to rights, wiping the reflexive tears from his eyes.

"Blimey, kid! If you wanted to kill me, there were less painful ways!"

"…Sorry."

"Thank Merlin for house elves, eh? Always listening in, the absolute miracles."

"Absolutely." Where would Harry be without them? Less well than he was now, that's for sure.

But Sirius was pulling himself to rights; in fact, he was pulling himself upright to lean more formally against the heavy armchair and waved his new, well-cared-for wand around to cast his own privacy charms before looking Harry directly in the eyes.

"Grimoires, eh, Crowley?" He paused, then muttered under his breath. "Yeah, I can get used to that." He coughed. "Grimoires, eh, Crowley!? That's a heavy topic to be bringing up so late in the evening?"

Harry furrowed his brows again. "Yeah, sorry about that. I just now learned about them, is all. I'll do my own research soon and all, but…is there anything you can tell me that won't be in the library?"

"Hrmmm." His godfather frowned. "I've looked into it for you already, actually. You're set to inherit literally everything else, of course – oh, except for a wee cottage for Moony – but I just can't will you the Black Family Grimoire, sorry kid."

"Oh, no, I didn't actually mean—"

"Can't even let you have a sneak peek, though even Kreacher was willing to help me research that. It will unquestionably kill you with a glance or a touch, pup; those bloody Blacks, you know how they were. It doesn't even like me much, and I'm the hei—Head, now."

"No, no. Really. You've given me more than I ever needed as it is," Harry deflected. "I was actually wondering if you knew about the Potter grimoire?"

"…Oh."

The sun was properly going down where Harry was now, so he cast a casual warming charm on himself as the long shadows in the room turned to the darkness of evening. It was comfortable enough to snuggle under the generously padded cushioned he'd conjured for now, the fabric soft and warm against his robes. Crow jumped from his seatback to Harry's shoulder, to nuzzle up against his chin and that familiar scent of dusty classroom faded away under the familiar scent of crow dander, feathers that had been near snow, and that elusive scent of wind that Harry always smelt on his bird-mentor.

Sirius, meanwhile, was now nibbling his thumb in deep thought, and Harry's heart lifted with a little hope that he might learn something of use.

"James never told me much," Sirius finally began slowly, thoughtfully. "It's generally not done, talking about the grimoire at all, you know. But he had access to it at Potter Manor before it burned down…"

Harry's heart fell.

"Of course, even cursed fire couldn't've hurt the Grimoire, they have too much personality to just sit there and let themselves be burned, but James never mentioned it after that…"

Harry's heart rose again.

"Course," Sirius went on thoughtfully, "if he did take it to Godric's Hollow, it might have the notes on what Lily did to save your life. Merlin! Now that's a thought worth having!"

Suddenly a thought occurred to Harry and he felt his stomach drop like a lead bowling ball. "Ah – if the Potter House was 'defeated in combat' – betrayal, firepower, whatever – it's not possible for Lord Thingy to have, have 'conquered' it somehow, is it?"

Sirius looked up. "Hrm?"

Harry found himself speaking faster and faster. "Like…like the Elder Wand who just goes with the winner? Just a very magical thing, but steeped in so much power that it has 'personality', its own preferences…? Can choose its own wielder?"

"Gods, no." Sirius assured him, and Harry found his muscles taut as he leaned forward to be reassured. "Grimoires don't bind to individuals, at any rate. They belong to the whole House, and all its primary generations. Nuclear family, whatever you want to call it. But why do you ask about this now, kiddo? Need more info for your special Defence classes?" Sirius rolled his eyes jokingly. "'Teacher' indeed. I can't believe Prongs' son is a teacher. Even your parents had the good taste to only descend to the level of prefect."

"I thought they were—"

"Head prefect's still a prefect," Sirius waggled a finger at him. Harry tried to ignore the smudge of whipped cream on the index finger fingernail. "You know you can't share the Potter Grimoire secrets with anyone, even if you do need ideas for class."

The sun had properly set now, its blazing orange glory hidden by heavy clouds on the horizon that let the pale afternoon light slip simply into grey. Without sunbeams to warm him up, the snowy winter landscape was radiating its winter chill into the darkened classroom now, and Harry suppressed a shiver.

"Nah, I'm only teaching for six more weeks anyway, and then the real Professor's going to be well enough to come back. It's just…it's one more connection to my family that I didn't realise I might have, you know? And," he blinked, "the thought has also occurred to me that maybe some of these other families have also willed me their Grimoires? The Cartwrights, or McAllisters or so on?"

"Harry, as I was saying—"

"But even house elves can take their instructions and… 'interpret' them in a way that suits them. The Elder Wand's old master doesn't have to be killed for it to prefer a new master, just disarmed; temporary incapacitation seems to be good enough for it to 'interpret' to its own convenience. If a Grimoire's got such a magical personality, then surely…I mean, even I have tossed up the idea of hitting Dumbledore over the head with a brick or something, so I could get a hold of the De—his wand, obviously I'd never do it, but if it comes down to a need for interpretation," Harry sought for the right words, "Well. That's just another form of Will, right? And Willing magic or transference of power or whatever is the very basics of magic, right? I…forgot where I was going with this."

Sirius' facial expressions had been going through all kinds of thoughtful contortions while Harry spoke, and as Harry's voice faded away, Sirius began to try and gave up on speaking at least four different times.

"You might have a point there," Sirius finally muttered, a look of deep introspection on his face. "Not about the defeat at combat thing, but the inherited thing – if it was in line with their family philosophies, if those witches and wizards who willed you their names meant to give you anything that would help you defeat You-Know-Who in future confrontations…You might need to do a proper check of your Vault, Crowley. Personally. Not all Grimoires would let house-elves touch them, if any do at all, of course. And maybe have your magnificent Mr Lloyd-Elliot get the Ministry to hand over the ruins in Godric's Hollow for a proper search there as well, just in case."

"Right." Harry nodded, brain whirling as he found himself with more things to do in an already busy year. "Sure. I'll…the letter can go to the lawyers' tomorrow morning, I'll need to add to my To Do list now before this conjured paper disappears with my notes…I might have to end the conversation here, Padfoot, and catch up with you another time."

"Sure," his godfather said, slightly bemused and rather thoughtful. "You do give me the most interesting of ideas, Crowley. Run along, then. Make your mischief."

The mirror went blank, and Harry was left looking back at his own surprised expression.

Then he stood up, dismissing his chair and his pile of cushions. He had over an hour before the bell rang for dinner, but his To Do list would grow quite a lot, and it was probably time for Crowley to switch out with Crookshanks as well.

Harry almost walked straight out the normal, regularly-used classroom door before something caught the corner of his eye: there, in the wall on his left where no door or doorframe had stood before, now existed a welcoming, hardwood construction. Dark oak, Harry figured from the look of its grain, with a House Black-looking bronze door handle and equally ornate bronze hinges.

He did a double-take but the door still remained.

"Ah…?" Harry said into the silent room. "Um…Kreacher? Is that you?"

The dark wooden door on its elaborate hinges popped open a few inches, inviting Harry into a smooth, wide and well-lit secret passage leading in the direction of the Gryffindor dorms.

"Merlin," Harry muttered, as his feet took him through the dark door and into the spacious, flat corridor. "House-elves really are bloody miracles. What would I do without you, Kreacher? You're an absolute marvel."