PoP 55

Perversion of Purity

Year 3: The Looming of Shadows

Chapter 13:

By ACI100

Disclaimer: This is a work of fanfiction based on the Harry Potter universe. All recognizable characters, plots, and settings are the exclusive property of J.K Rowling. I make no claim to ownership.

Acknowledgements: Thank you to my editor Athena, as well as my other betas 3CP, Fezzik, Luq707, Raven, Regress, Thanos, and Yoshi89 for their incredible work on this story.

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October 14, 1993
Severus Snape’s Office
9:12 PM

Harry gasped, forcing Snape from his mind. The room whirled around him. Bloody hell. Dumbledore had always attacked conservatively, judging Harry’s abilities and probing accordingly. Snape was different; his strikes were fast and hard, over and over again.

There had been a time when Harry worried whether it was attempted sabotage and had almost gone to Dumbledore. Remembering what the man had said about the Dursleys stopped him. He puts too much faith in people he trusts; he would probably support Snape no matter what.

Harry had instead gone to Grindelwald, who had been pleased. Snape’s methods were aged and had fallen out of favour, but they were the ones Grindelwald preferred.

“The flaws are not in the forging, but in the tools. It is the most efficient way of sharpening the mind, yet some are inferior and unable to cope, and the whetstone proves too harsh.”

It reminded Harry of the way Grindelwald talked about Durmstrang — a school where the weak failed but the strong succeeded. While Hogwarts focused on producing as many competent magicians as it could, Durmstrang yearned for exceptionalism and cared naught how many pupils it broke or discarded.

“That will suffice.” Harry could hear Snape was just feet in front of him, but his vision swam so violently he could hardly discern his outline. “You have practiced diligently.”

Harry blinked the dizziness away. “Am I on schedule then, sir?”

“Do not fish for compliments. You and I both know that despite your numerous flaws, you have an intuitive grasp of magic that most could only dream of. You are merely avoiding the squandering of that talent.”

So I’m at least on track, probably ahead. I doubt he would have snapped that hard if I wasn’t ahead. Harry suspected that, no matter what he did, Snape would never like him. His loss; that’s not my problem. It mattered not — all he cared about was progressing. I’m not sure how I wouldn’t be with Grindelwald pushing me so hard.

Trusting Grindelwald still felt mad, but it no longer bothered him. He needs me and we both know it — he really will do anything to help. And why not? Grindelwald yearned for a better world; that was worth almost anything.

Harry paused. I’ve never thought like that before… not that bluntly, at least. He supposed it was no surprise. I’ve always agreed with most of what he says, just now how he went about things.

Five days earlier…

Woven mosaics faded along with marble walls and high, vaulted ceilings. Harry blinked and was no longer in the tunnel miles beneath Rome. Now he stared around Grindelwald’s tower cell, out the window and towards brewing storm clouds rolling over a dark, grey sea.

“So that was the Suicide Curse?” he asked, remembering the etched incantation that Grindelwald had studied, trying himself to remember it.

Dolore Opprimendo

“Yes and no.”

Harry frowned. “What do you mean yes and no? I thought it was a yes or no question.”

“It was composed like one, but the truth is neither.”

“What is it, then? The truth, I mean?”

“The truth is that men are malleable things, their minds most of all.” Harry kept staring, waiting for more. “I once armed my men with what they later called the Suicide Curse. People were beginning to wonder why important men around the world began taking their own lives. I gave them a spell whose effects explained anything, but their results were not quite so spectacular as mine.” Grindelwald folded thinning hands across his bony chest. “Do you see it yet?”

Harry nodded. Clever. “You lied. The spell you gave them wasn’t the one you used.”

“I did not lie. I only obscured part of the truth. The spell I armed them with was of my own creation. It projects powerful negative emotions.”

“But it wasn’t the original spell?”

“No, only a derivative. The original spell amplifies, not projects.”

Harry furrowed his brow. “What’s the difference? That sounds like the same thing.”

“The difference is that external forces are easily recognized and easily defeated. The spell works in short bursts. Enough to incapacitate, but not to truly alter one’s mind. It is a painful bite, whereas the original is a parasite whose effects linger and strengthen. The uneducated may think they sound the same, but the enlightened know the difference is as stark as night and day.”

I’ve never meant someone so good at answering questions without actually answering them. Harry thought it was Grindelwald’s way of testing him.

“I think I get it. Can I ask you a couple of other questions about magic? They don’t have anything to do with the memories.” Grindelwald remained still. He really doesn’t like when I ask if I can ask things. “How do rituals work?”

“Often poorly.”

“Someone brought them up to me recently and said they could be used to change things like pain tolerance.”

“They could. I could study rituals for a hundred lifetimes and never learn them all, yet I do not need those lifetimes to know that most are unwise.”

“You make it sound like they don’t work.”

“They work, just not in the ways some fools hope. The rituals you’re speaking of alter the mind, the body, or how the latter’s relationship with magic.”

“Like how you said we’re conductors.”

“Precisely. Most rituals of this nature make minute changes. One may, for instance, quicken their perception of motion.”

Harry’s pulse quickened. “That would be dead useful in a fight.”

“It would, but another may offer a very slight increase in how much magic your body can conduct. Which do you think is more useful?”

“The first,” Harry answered at once.

Grindelwald raised an eyebrow. “Why?”

“You explained ages ago that power isn’t that important and only matters when using magic most people would never have any reason to cast.”

“That is not entirely true. Better conductors do tend to fatigue more slowly, but yes, the impacts are minimal.”

“So am I right?”

“You are, but not for the reason you proposed.”

It couldn’t be that easy, could it? “What other reason is there?”

“The more meaningful the change, the more they must give up to attain it.”

Harry shivered, goosebumps sprouting along his arms. “Sacrifice,” he muttered. “My friend mentioned sacrifice.”

Grindelwald nodded. “This is old magic in its purest form, born before the days of wands and incantations.”

“Is this like how you said some people think magic was just about thoughts at one point?”

“It is similar, yes.”

“So… what sorts of things would you sacrifice?”

“Blood, almost always blood, but that is rarely all. Many rituals can be done with minimal cost, but many more cannot. If one wanted to increase their conductivity by even the smallest of margins, it would cost them dearly.”

Harry swallowed hard, discarding half a dozen ideas as neck hairs stood on end. If the cost for something like that is so high, are they even worth it?

“There is also volatility to consider,” said Grindelwald.

Harry blinked; he had become lost in thought. “What?”

“Old magic like this is volatile. Its nature is to change in ways that should not be possible. Some would even call it a violation of nature itself. Nature rarely tolerates those who break its laws.”

“When you say volatile…”

“The greater the change, the higher the risk.”

“Have you ever done rituals?” Harry asked. They’re really starting to sound not worth it.

Grindelwald met his gaze unblinkingly. “I have.”

“But you just said—“

“Something volatile need not explode if handled carefully. I rarely partook in rituals whose effects were immediately noticeable, but I did push the boundaries of ritualistic magic the same way I did most other forms.”

“How did you do it?” Harry asked.

Grindelwald studied him. “With great caution and a deep understanding of the balance one must strike.”

“Is it worth it? Can you teach me how to do it safely?”

“In time.”

That surprised him. There had been Grindelwald’s delayed sharing of the Suicide Curse, but he never held back practical magic this way. He must have a reason; it’s not like anything I say will change it.

“There was one other thing.” Grindelwald waved a hand and Harry began explaining everything he had heard about Astoria Greengrass and her strange condition.

Grindelwald listened intently throughout the tale. “That is interesting,” he mused. “I have never seen its like before.”

Harry’s heart sank. “You haven’t?”

“It sounds reminiscent of accidental magic, and of what Ariana Dumbledore became, but there are meaningful differences.”

“Did you ever find out what was wrong with her?” Harry asked. “Ariana, I mean.”

“She was broken by the muggles and their cruelty, so afraid of who she was that she suppressed it with all her being. Any magic clinging to her was buried deep within, condensing in ways that are otherwise impossible. She developed what is called an Obscurus and thereby became an Obscurial.”

Hot knives twisted inside his stomach. His chest burned, filling the back of his throat with scolding bile. Damn the muggles! Damn all of them! So much would be better if we stopped giving them power…

Harry made himself focus. “So you think she’s an Obscurial?”

“I did not say that, merely that there are similarities. Learn more of her and perhaps I will be able to offer you more.”

Back in the present…

“How well have you adapted to using the time turner?”

Snape’s sudden change of topic caught Harry aback. “A bit.”

“And how strictly have you followed the ministry guidelines for dictating when the device should be used?”

Harry met Snape’s eyes. “That depends, Professor. How much trouble would I be in if I hadn’t?”

Harry thought, just for a moment, that he saw amusement flash across Snape’s face, but it was gone in an eye-blink. “The ministry would be most displeased with you if they discovered any exploitation.” Snape’s lip curled. “I personally am not foolish enough to believe you have not used the device for your own gain and think that information might as well be made useful.”

Harry mussed his hair. “I’ve started using it more out of classes, but only in the past two or so weeks and only to practice magic.”

“And I assume the drain is significant?”

“It isn’t too bad if I don’t have to pull another double that day for classes, but doing it twice in a day…” he grimaced.

“Fortunately for you, Potter, I believe we have reached the point at which I can begin teaching you not only to defend your mind, but to augment it.”

Harry’s heart leapt. “Do you mean you’re going to teach me Passive Occlumency, sir?”

“I will not hold your hand through the process if that’s what you’re asking. I will arm you with the necessary tools to begin mastering a given technique and we will check in each week.”

Harry tried keeping the grin off his face. Good. I’d rather not waste too much time on something I’ve already been doing with Grindelwald, but having someone in-person to help should speed things up.

October 23, 1993
The Library
8:17 PM

An owl hooted outside the window. Harry looked up. The sun had set, casting the library into shadow. His corner was among the darkest in the room; Voldemort’s journal would be unreadable if not for a flickering candle nestled on his desk.

It was the first time they had written since their first communication and, again, Voldemort was on about the Chamber of Secrets.

The waterfall is there for more than aesthetic appeal. I think it’s something you might want to investigate.

Weird… I never expected him to just give me answers. I have to stop expecting him to be like Grindelwald… they think so differently. Harry looked back down at the journal. I guess this meeting won’t be the last thing I do tonight.

Harry felt the detection ward trip and slid the journal off the table and into his bag, plastering what he hoped was a casual expression on his face.

Harry looked up, surprised by what he saw. “Sorry,” said Astoria Greengrass, blushing. “I didn’t mean to startle you. I know I’m early and can leave if you’d like, I just—“

“It’s okay,” said Harry, forcing a smile. This feels off. The ward gave no further signals; no one else was close. Weird. “I just didn’t expect you almost fifteen minutes early, that’s all.”

Astoria was still blushing. “I finished dinner early and had nothing else to do.”

I was not ready for this… Harry had expected a miniature Daphne, but this girl was anything but. Daphne would never have been caught dead lying so poorly, nor had Harry ever seen her look so nervous.

“I see,” he said, trying not to fidget. It would have been easier if she was like Daphne, at least I would know what I was working with. His heart was beating a bit too fast, his stomach tight and restless. This is a lot more stressful talking with someone new… I’m still not the best at that. Miles better than he had been two years ago, but still it made him anxious. studying her. Head in the game, Potter… “You look surprised.”

Astoria shuffled in her seat. “When Cassandra Yaxley told me that she was setting up tutoring, I didn’t expect it to be with…” she trailed off.

Harry offered her a thin smile. “The Boy-Who-Lived, or the boy your sister’s probably told you is the next dark lord?”


Harry actually laughed. I didn’t expect that answer. Astoria’s shoulders relaxed. Good. “For what it’s worth, I’m not your sister’s biggest fan, so I’m not surprised she says things about me. You seem more genuine.”

Astoria looked away from him. “She’s complicated.”

“That’s one word for it.”

“She’d be really angry if she knew I was sitting here and talking with you.”

Harry raised an eyebrow. “I don’t see you leaving.”

Astoria set her jaw. “Daphne isn’t the boss of me.”

No… it can’t be this easy. “So you’re not going to leave or tell her about this?”

Astoria shook her head. “I need to learn.” Something rabid raged behind her eyes.

“You’re sure?” he asked, mustering the most concerned expression he could, learning out across the table. Make it convincing. “I don’t like your sister, but I don’t want to cause any trouble. I can probably find someone else to tutor you if—“

“No!” Astoria clapped her hands to her mouth, looking around, horrified by her outburst.

Harry smiled again. “You don’t need to worry about that. There are Silencing Wards up around us.”

“What if Daphne walks in here?” That’s got her paranoid now. “She likes spending time in the library after dinner?”

Harry slid his wand from his sleeve. Let’s hope I can actually pull this off. He concentrated and felt the ward take effect. “Handled,” he said. “There’s now a Notice-Me-Not Ward around us.”

Astoria gaped. “You didn’t say an incantation!”

Harry ran a hand through his hair, trying not to grin. It felt good seeing her look at him like that — nonverbal magic was a nightmare. “Yeah, I’ve been working on that. I still can’t do it for every spell, but I’m getting better.”

Astoria looked awed. “Isn’t that super advanced magic?”

“It’s taught in sixth year. Most people get the hang of it eventually.”

“So this is why they partnered me up with you.”

“Don’t say that yet. I’ve always been good at magic, but I’ve never actually taught it before. I could be rubbish for all you know.”

“It can’t get any worse,” she muttered, looking down towards the desk.

“Nonsense, your sister could start pestering you about that, too.”

It was a gamble. I can’t push too hard, I’m sure she likes Daphne, but she really doesn’t like being bossed around by her. It was an obvious button. Merlin, I wonder if I was this naive at eleven… was it this easy for Lucius Malfoy?

“She actually hasn’t done that,” Astoria was saying. “She understands that…” she trailed off, suddenly pale.

So there really is more going on… a lot more. “Your sister understands lots of things. She’s smart, I’ll give her that.” He looked around the room before sharing a conspiratorial glance with Astoria. “Tell you what — I won’t go blabbing to your sister about these tutoring sessions if you don’t.”

Astoria smiled for the first time. “Deal!”

Elsewhere in the library…

“I’ve found it!” Hermione said at long last. Ron jolted, suddenly alert.

“The Patronus Charm?”

“Yes, come here!” He scrambled around their table and looked down at the page she was indicating.

There it was.

It felt surreal seeing it after two weeks of searching — there had been times when he worried it was just too obscure to be found.

“Expecto Patronum,” Ron muttered, running his finger along the words.

“I await a guardian.”

Ron frowned at her. “Uh, I’m sorry to hear that?”

Hermione swatted him on the arm. “It’s the translation, Ronald.”


“The original spell is in Latin.”

“What does this bit mean?” Ron asked, indicating a passage saying something about emotional manifestations.

Hermione chewed her lip. “I don’t know,” she admitted. “The dementors feed on emotions, so it probably has something to do with that.”

Ron shrugged. “Should we go practice, then?”

“This doesn’t seem all that helpful.” Hermione sounded personally offended. It’s like she can’t believe the book doesn’t have an essay about it. “It just gives the incantation and what the spell does.”

“What else is there to give? Isn’t that sort of just how magic works?”

Hermione rubbed at her eyes. “It seems too simple. You heard the seventh years we asked about it, they all said it was super complicated.

“They also didn’t know the spell, so not sure I trust them.” Hermione looked unconvinced. “You worry too much, Hermione. They wouldn’t write about the spell and then just purposefully leave out how to cast it.”

“Maybe,” she said, fingering the page.

Ron grinned. “Time to practice?”

Hermione sighed. “Yes, I suppose that’s best.”

Sometime later…

The sound of stone grinding against stone faded, its ghost echoing down the corridor behind him. Ahead loomed the Chamber of Secrets with its vaulted ceiling and dark arches made from stone. Shadows crawled up all four walls and the basilisk’s corpse still sprawled across the floor.

It had taken Harry’s breath away the first time he had explored; it wasn’t like he had absorbed much while fighting for his life.

He paused at Slytherin’s feet, looking up at the stone-carved face. “Speak to me, Slytherin, greatest of the Hogwarts four.”

The mouth opened, a ramp descending upon his next command. Harry climbed through and into a vast stone room that reminded him of a cathedral with its high ceilings and circular walls. Nothing new here. He had decided during his last visit that this was where the basilisk must have slept.

Harry walked down the hall and into another chamber, its floor sloping down to the edge of a pool large enough for even the giant squid. A dark blue waterfall poured from the carved head of a hissing basilisk.

It’s beautiful. Harry shook himself, trudging through the water and wishing he had a spell to keep it off of him. His trousers weighed him down before he reached the waterfall and, by the time he stepped through, his robes were sopping west.

If Voldemort’s right… Harry frowned, faced with naught but a blank wall of stone. No… not blank, something’s carved there.

Harry squinted, lighting his wand. Two snakes coiled tightly around each other, faint against the weathered stones.

Clever. “Open.”

The wall slid noiselessly aside and Harry stepped across the threshold, pausing when the wall closed shut behind him. This was not what he had expected.

Merlin, he thought, looking around at what could only be Salazar Slytherin’s personal study.

Author’s Endnote:

I will just confirm right now that nothing in the chamber will function as an easy power-up. It’s a fun bit of worldbuilding, not a major plot device.

Please read and review.


PS: The next password will be released in one week. THE NEXT TWENTY-THREE CHAPTERS ARE AVAILABLE FOR PATRONS RIGHT NOW, AND THEY WILL ALSO RECEIVE CHAPTER 79 TOMORROW! If you want to read all these chapters early, sign up to my Patreon page — https://patreon.com/ACI100

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