[From Samhain to the Solstice]: Mirror of a Thousand Shadows, Harry/Tom, Ginny/Bellatrix, AU, 3/4

[lomonaaeren]

Thank you again for all the reviews! I have decided, as this story has grown far beyond the bounds I originally planned for it and would probably need another 60,000 words or so to do justice to the plot I want for it, I will be ending this story after the next chapter and continuing with a sequel at some further point in time. Please notice the change in the tags and ratings.

Part Three

Tom woke up on Christmas morning and stretched in his deliciously warm bed. There were no other first-year Slytherin boys who were staying, which meant there was no one else to disturb him with squabbles or trying to use the bathroom early.

It had scandalized his parents when he decided to stay for the holidays. Mother had written him a long letter in which she had told him to come home with your bothers, young man, and hadn’t ever once used his name. He was “young man” or “boy” to her, and, well, she already had so many more of them, didn’t she? And none of them had been supposed to be a girl.

Tom hadn’t bothered answering. His refusal was its own kind of answer. And Tom intended to stay at Hogwarts for the Easter holidays, too, so he wouldn’t need to face up to his family’s disappointment until the summer.

They probably would have forgiven him by then, anyway. Tom made a face at the thought that it might even give his parents time to make the girl they’d always wanted.

Tom sat up and fluffed his pillow into place. He’d slept better since getting rid of the diary, even if it meant that he missed Ginny. And he hadn’t any more bouts of losing his memory, which he thought was just a sign of how smart his decision had been.

He had a small pile of presents at the foot of his bed. The jumper that his mother always knitted, of course; even Harry got one of those each year. Chocolates from his father. A wand polishing kit from Bill, which made Tom smile a little. At least Bill had noticed how proud Tom was of his wand when he visited that summer.

A book on defensive spells from Percy, and one on dragons from Charlie, which would be useful enough. A gift from the twins that was humming and squeaking, which Tom Levitated and destroyed with a burst of flames when it was in midair. A comb from Ron, which made Tom roll his eyes. Ron had probably remembered at the last minute that everyone was supposed to get each other a gift, and scrambled through his own things to find this.

And a slim present wrapped in bright green and silver paper that made Tom stare. No one in his family would have willingly done that for him, and he didn’t expect anything from anyone else. His fingers were shaking slightly as he opened it.

A small tag fell off, and Tom snatched it up.

Happy Christmas, Tom!—Harry.

Tom smiled a little. Of course it was from Harry. And Harry had used his name. Harry didn’t mind it if Tom stayed here, and he’d probably chosen a present that was what he thought Tom would like.

Tom kept smiling even as he opened the gift, prepared to like it if even it was another comb.

It was not. It was a Sneakoscope.

Tom stared at it with wide eyes. He didn’t know how expensive they were, but he knew how useful they were. He caressed the side of the glass spinning top and imagined where Harry would have got it.

He must have owl-ordered it, because Harry was too young to go to Hogsmeade. He had thought about what Tom would like and he had ordered it and it had come in time for Christmas. He had to have been thinking about it for a fortnight at least.

Tom touched the glass top reverently. It didn’t light up, but then, of course, his roommates were all away. Tom planned to carry it with him—safely wrapped-up—to class, and hopefully it would alert him before someone could prank or jinx him.

Harry thinks about me.

That was more precious than any amount of Galleons (although Tom wouldn’t have turned them away if Harry had offered them). And Tom was only a little distracted with the realization that he hadn’t bought a Christmas present for Harry in return. He still had time, before the end of holidays, to give him something.

To show that someone was noticing and thinking about Harry, too, and not Harry the Boy-Who-Lived or Harry the potential Leonismouth or Harry the unusual Slytherin who probably should have been Sorted into Gryffindor instead. Just Harry.

*

Harry eyed the diary. He thought it eyed him back. It had certainly tried to get him to write in it, or so he thought, wriggling enticingly at him and flipping its pages back and forth. It had jumped from the ground (and then flopped back again) when Harry had dragged it into this appearing-and-disappearing room and a quill had fallen from his robe pocket.

But Harry had looked into it and seen that it seemed to be correspondence between Tom and someone named Ginny. That had made him immediately put it down again. He didn’t want to intrude on Tom’s privacy when Tom seemed to have little enough of it in the Burrow.

And with him constantly getting letters from home and questions from his brothers about why he Sorted into Slytherin. At least Ron had stopped after Harry had told him how much it annoyed Tom, and by extension Harry.

The room that had opened was made of white stone, with torches spaced evenly along its walls, and shelves full of books that made the air feel heavy and thick, suspiciously like the books in the Restricted Section. There was one chair, in front of a spacious fireplace, to sit, and a table with a drawer where Harry had stuck the diary.

But more to the point, when Harry had walked into the room for the first time, carrying the diary, his scar had immediately stopped hurting.

Harry didn’t know why. He thought it could be a property of the stone that sheathed the room, or the magic of the books, but the simplest explanation was that it was the room itself. It seemed to respond to the thoughts and desires of the people who found it.

Harry had left the diary in the room and exited it, watching as the door vanished behind him. Then he had paced back and forth the way he had when he was trying to figure out whether the diary caused his scar to hurt—three times seemed to do it—and wished for a place where he could fly.

And he had opened the large blue door that appeared to find a room with a ceiling overhead that seemed to be higher than the Great Hall’s and a grassy pitch that at least seemed to sway in the wake of a breeze that Harry could also feel on his hands and feet.

It was amazing.

Harry had left the diary hidden in the version of the room that seemed to make his scar stop hurting, but he had also come back. He had no idea what it was, but he wanted to. And he was sure that it was somehow connected to the attacks by the Heir of Gryffindor, but he didn’t know exactly how. It wasn’t as though an eleven-year-old’s diary could actually be the Heir of Gryffindor, and Tom being that was laughable.

Maybe. Harry thought. After all, Tom had managed to blackmail people years older than he was…

But then Harry shook his head. No. Among other things, he spent a lot of time with Tom, and Tom had never made his scar hurt. It had to be something that the diary had been around, or the diary was connected to the Chamber of Courage somehow. Was it something that used to belong to the Lady Firebrand, maybe?

That had made more sense. But it didn’t tell him much about the diary. He could learn more if he read it or wrote in it, he supposed, but he didn’t want to invade Tom’s privacy. And he had no idea how to go about investigating something that wasn’t anything like anything he had heard of in his first two years of Hogwarts.

“I wish I knew what you were,” he said aloud, scowling at the diary.

There was a soft, abrupt pop to the side of him, which had Harry spinning around and aiming his wand. In his experience, abrupt noises were rarely good news. They were either Snape arriving to try and get him in trouble, Draco Malfoy arriving to try and get him in trouble, or the Weasley twins showing up with a “hilarious” prank.

But the pop had sounded and then disappeared, and a new book was lying on the hearth of the fireplace. Harry approached cautiously, wand still drawn. He was prepared to blast the book with fire if it made his scar hurt, too.

It only lay there, though. Harry picked it up and turned it cautiously around, noticing that it seemed to be bound in heavy dark leather, wrinkled like it had been dropped in the bath.

Secrets of the Darkest Art.

*

“Harry! Thank you for my Christmas gift.”

Harry started and looked up. He was one of the few older Slytherins who had remained over the holidays; Draco Malfoy had, too, but he was too smart to bother Tom anymore. He might doubt that Tom knew all about what kind of plush he cuddled at night, but he didn’t doubt, wisely, that Tom was the sort who would spread that all around.

(It was a stuffed dragon. Tom had snickered so loudly that he’d almost given himself away).

“You’re welcome, Tom. I hope you enjoy it. Just don’t take it to Potions. It’ll scream so loudly because of Snape that you won’t be able to hear his instructions.” Harry smiled, but it seemed like his heart wasn’t in it.

“Are you all right?” Harry had seemed pale and withdrawn the last few days, from what Tom remembered.

“Yeah, I…”

Harry dragged his hand through his hair. Tom sat down on the couch opposite him, studying Harry. He had sneaked into Ron’s bedroom over the summer and studied the photographs in the photo album that Harry had brought with him, too. He actually didn’t think Harry looked as much like his parents as everyone said. For one thing, they smiled a lot more than he did.

“You can tell me, you know,” Tom coaxed softly, and cast the little spell that would destroy any Eavesdropping Charms that were trying to listen in.

“I want to,” Harry said, which was unexpected enough that Tom blinked. “But I don’t know if I should. It’s pretty disgusting, really, and you’re just a kid.”

“I’m only one year younger than you,” Tom said, in the level voice that he had found worked best to make his brothers listen to him. At least, his older brothers. The twins never listened no matter what, and Ron would have just invited him to play another game of chess.

Harry breathed out. “That’s true,” he muttered.

“What is it?”

“Something you can’t tell anyone else.” Harry abruptly narrowed his eyes. “Look, Tom, I know that you’ve done some pretty cunning things to get the other Slytherins to leave you alone. And I can’t pretend that I’m some kind of moral Hufflepuff who’d report you to the professors for that. But you have to promise to keep this secret.”

Tom felt a sharp thrill run down his spine, in a way that he had never thought he would get from someone else essentially threatening him. But then, this showed that Harry took him seriously and thought he was dangerous, or could be dangerous if he released the secret. And he would trust him with that secret anyway, as long as Tom promised. Here was the gift Tom could give Harry to repay him for the Sneakoscope.

“I do promise,” he said. “I can make a wand oath if you want. But if you do start hearing about it from someone else, then you’ll pretty much know it was me, and you can decide how you want to retaliate.”

Harry’s smile was fleeting. “Merlin, Tom,” he said, and then sighed. “When I was coming back from visiting Ron the other day, I discovered something that made my scar hurt.”

Tom straightened at once. The only things he really knew about Harry’s scar were that it supposedly came from the backlash of the Dark Lady’s Killing Curse, and that it had something to do with an adventure Harry and Ron had had at the end of last year. Even then, he only knew that last part because he’d heard them whispering about it, without details.

“What was it?”

“A small black diary.”

Tom’s breathing sped up, and Harry appeared to notice. He raised his hand. “Look, I haven’t read it. I got close enough to see that it had your handwriting and name in it, and I backed off. I haven’t invaded your privacy. But at the same time, I was concerned, because, well, it did make my scar hurt.”

“Um,” Tom said, a little dazed. He didn’t know anyone else who would have respected his privacy enough not to investigate a potentially dangerous thing.

Why has no one else in our House tried to befriend Harry? Why can’t they understand that he could be the best friend anyone ever had?

Then again, it wasn’t Tom’s fault that their Housemates were stupid. He put that thought aside. “Thank you,” he said quietly. “What happened after you found it? Did you write in it?”

He chided himself a second later for a stupid question, because Harry had just said that he hadn’t looked at it, but Harry shook his head. “I was pacing back and forth, trying to see why it would make my scar hurt and if that was really the source of it, and then—then another door opened across the hall from me.”

Tom straightened again. “The entrance to the Chamber of Courage?”

“What?” Harry blinked at him. “No.”

“Oh.”

“Do you believe I’m the Heir of Gryffindor, then?”

Tom wouldn’t have needed to be as smart as he was to know what Harry was feeling then, with the way he was visibly drawing back from Tom and folding his arms. “Not at all,” he said quickly. “But I think the Chamber of Courage must have something to do with the Dark Lady, since she was supposed to be Gryffindor’s descendant, right? And if your scar was hurting, maybe it could lead you there?”

Harry slowly uncrossed his arms. “Oh,” he said. “Okay.”

Tom just barely kept himself from shaking his head. To think that he’d assumed Harry was wildly popular and would be hard to get to know because of that! True, he’d had some people sitting with him at the beginning of the year, but the way they’d all withdrawn over the Heir of Gryffindor rumors made it clear that they’d never been true friends.

Harry gave him a warm smile, and Tom basked in it.

“It was a strange room I’ve never seen before,” Harry went on, his brow wrinkling. “I took the book into it, and it made my scar stop hurting. I thought it was awfully odd that a place like that would appear just when I had found the diary, so I did some tests. I don’t think it’s connected to the diary, though. It opens up different rooms if you pace back and forth in front of that wall three times thinking about it.”

“What kinds of places?”

“I was able to turn it into a Quidditch pitch.”

“Wow.”

Tom sighed the word, and saw Harry smile at him. “It’s nice to know that some purebloods can still think of magic as wondrous even though they grew up with it,” Harry murmured.

Tom would have done a lot to keep that smile, but it faded quickly. “And that’s the secret you want me to keep? About the room?”

“No.” Harry scratched at his scar.

They sat in silence long enough that Tom would normally have got impatient, but it was so obvious that Harry still hesitated with trusting him. That was a sign of good sense Tom approved of, even though he also intended to have Harry confess all his secrets eventually.

And I’ll be the best confidante ever. Better than Ron.

“You can ask the room for other things,” Harry went on, his hand clenching at his side for a second. “I found that out accidentally. I was trying to figure out how to understand the diary, and the room showed me a book…”

“About the diary?”

“Not exactly. About the kind of artifact the diary is. And I’m sorry, Tom, but I am going to ask for a wand oath.”

Tom wasn’t bothered. He had known they would get there eventually. He took his yew wand out, and Harry nodded and removed his holly one from the holster along his arm. They reached out and touched the tips of their wands to each other’s.

A sharp spark ran down Tom’s arms, and he gasped. A golden light welled in between their wands, and from Harry’s wide, eyes, he wasn’t the one who had started it either and had no idea what it was.

“Wh—what—did you get your wand from Ollivander’s?”

“Yes,” Tom said, with a frown. “But I’ve had someone else make a wand oath to me, and it didn’t react like this.”

Harry gave him a look which Tom pretended he didn’t see. And Harry still didn’t ask about who Tom would have made a wand oath with, which Tom thought was awfully decent of him. “Well, then maybe it’s the wood they’re made of, or the order they were made in. Or the cores.”

“Mine’s a phoenix feather. Ollivander said that the phoenix which gave it had only given one other feather, and he was surprised to sell my wand so soon after the other one. Do you think…?” Tom trailed off, staring at Harry’s wand.

“He said the same thing to me. Phoenix feather, only the second feather donated.” Harry smiled at him. “Brother wands. I read about that in our history textbook, but I didn’t know it was real.”

Tom made a mental note to himself to read the History of Magic textbook more regularly. Apparently it had information in there other than goblin rebellions. But the note was only a literal footnote to his rapidly growing excitement.

Brother wands. I have brother wands with the Boy-Who-Lived.

Harry had had already looked at him kindly, and then respectfully because he thought Tom was dangerous and he didn’t want to invade his privacy, but now he looked at him with a tilted head and bright, speculative eyes. Tom smiled. This was the kind of look he wanted to collect and keep for always, and keep growing.

“The nice thing about brother wands,” Harry said, and he looked as if he didn’t know whether he wanted to smile or frown, “is that a wand oath made with them can’t be broken. It’s not like an Unbreakable Vow, where it would kill you. You just won’t be able to take the action or say the word that would break it.”

Tom smiled slowly. Something to keep in mind for the future, when he had something he wanted Harry to vow. “Good. Then you know you can absolutely trust me with the secret of whatever this book is, and whatever this diary is.” He paused. “Aren’t you going to ask me what I wrote in it?”

“Not unless you want to tell me.”

Merlin, how did an honorable sod like him ever get into Slytherin?

But Tom was pretty sure he knew. Harry was quiet and self-contained, for all that people seemed to think they knew him because of his reputation. He kept secrets well. He didn’t go around offering free tutoring help to all the first-years the way he had with Tom. He had the potential to do good, but he wasn’t a do-gooder.

There’s more than one way to be a Slytherin, Tom thought. Even if he personally thought he was better at it than Harry.

“I swear,” he added, “that I will keep the secret of the appearing and disappearing room, of the diary that makes Harry Potter’s scar hurt, and of whatever he wants to tell me related to them. I swear it on my wand.”

The golden light that had been welling from their wands abruptly extended into a long sheath of light that completely surrounded them, and even surrounded the pair of them, surging around their feet, arms, and the couch. Tom nodded as it faded.

“Okay,” Harry said. “Have you ever heard of Horcruxes?”

*

“That’s disgusting.”

Harry nodded, comforted by the way that Tom was glaring at the diary. They stood in the Appearing-Disappearing Room, as Harry was calling it for lack of a better name, in the form that contained the diary and made sure his scar didn’t hurt. Tom had read a few sections of Secrets of the Darkest Art for himself, and had put down the book like he wanted to wash his hands.

“I can understand wanting immortality,” Tom went on. “Like I can understand wanting fame and greatness.” He glanced quickly at Harry, who just raised an eyebrow at him. “But I don’t understand doing something like that.”

Harry nodded. “Killing someone else? Disgusting.”

“Plus you could get caught.”

Harry had to smile. Yes, he and Tom didn’t always have the same priorities, but frankly, Harry didn’t think they had to. And if Tom sounded shocking and greedy for his age sometimes, well, he’d grown up in a family where people wanted him to be something else. No surprise that he’d decided to be as different from a “typical” Weasley as possible.

“Has the diary tried to get you to write in it?”

“At first. It popped open, and that was how I saw your handwriting. And then it did it a little after I brought it in here for the first time. But it hasn’t done anything more than that.” Harry hesitated. “What did it do with you?”

“I wrote my thoughts in it at first. Then it started responding.” Tom just shrugged when Harry let out a low hiss. “Yeah, I know. But it was powerful and she said that I was the first person in years who had the magic to awaken her, so—”

“She?”

“The person, or the memory, in the diary. She said her name was Ginny and she was a Hogwarts student at one time. Years and years ago. She said she was in Gryffindor and her Head of House was Dumbledore, so it was probably a few decades ago. And she’s brilliant.”

“Oh?”

“Her explanations of magical theory,” Tom said, in the kind of reverent voice that Dudley used to talk about birthday presents. “They’re utterly sophisticated, and so much easier to understand than the professors’. And she taught me more history than Binns ever could.”

Harry sucked in his breath. He didn’t know why the idea made sense to him, but it did, and it leaped into his mind in the way that the idea for how to succeed at Transfiguration had.

“The Lady Firebrand is said to be brilliant at magical theory, too,” he said quietly. “And she would presumably know history. She shaped so much of it, didn’t she?”

Tom turned to stare at him, and Harry could see that he was honestly startled. It was hard to see through all of Tom’s ploys and masks, but the surprise in his eyes was too bright to be faked, Harry thought.

“What? No!”

“Think about it,” Harry said softly. He hated the note in Tom’s voice, but he was going to push. “There aren’t that many people who would make Horcruxes in the first place, for the reasons we just talked about. But the Lady Firebrand didn’t mind killing people or trying to—kill a baby. And is it a coincidence that the Chamber of Courage opened when this Horcrux was floating around?”

Tom backed a step away from him. Harry remained where he was, studying him. He didn’t know for sure what Tom was feeling at the moment, but he knew it would be a bad idea to go after him.

“It’s not her,” Tom snarled, sounding wounded.

“It’s a guess, not a fact.”

“It’s not. Ginny was normal! I mean, normal for a brilliant student. There’s no way that the Lady Firebrand was ever—” Tom cut himself off.

“It may not be her,” Harry said, even though he was convinced as it was. “We certainly didn’t know everything about her. I never heard her real name. But that means it could be Ginny. And who else would have the power to open the Chamber of Courage, but the real Heir of Gryffindor? We know that the Lady Firebrand always did claim that heritage.”

“You’re lying.”

Tom’s hands had folded into fists. Harry carefully wrapped his right hand around his left arm, ready to draw his wand from its holster. He didn’t know for sure if brother wands could duel against each other, but Tom looked dangerous, right now.

The moment wavered and faded back and forth for a second. Harry didn’t blink. He had the odd feeling that he would lose Tom forever if he did.

And he didn’t want to, for all that it seemed obvious to him that the Lady Firebrand had made Horcruxes and infected this diary with her spirit.

Tom stood up straighter and stared at Harry. “I want a wand oath from you, too,” he said harshly. “That you’ll never tell anyone, if it is her—I’m not saying it is—that I got tricked into helping her.”

Harry blinked, glad for the moment of disorientation so that he could control his urge to laugh. Then he really would lose Tom, he was sure.

But really, he should have suspected something like that. Tom hated to be overlooked, and he would hate to look weak, too. Harry could have said a lot about how a Horcrux would be an unusual artifact and no one would blame Tom for being tricked by it, but instead, he just nodded and drew his wand, slowly, so that Tom wouldn’t think he was about to cast at him.

“Do you want to do it now?”

Tom contemplated it silently for a moment. Then he drew his wand and came up to lay it across Harry’s. Harry concealed a sigh. He didn’t want to admit the warmth that flowed through him when Tom’s wand was touching his. It would seem pathetic to someone who had always had a large family and disdained most of them, probably.

“Swear that you’ll never tell anyone I was tricked by the diary Horcrux, either by word or in writing.”

“I swear that I will never tell anyone that Tom Weasley was tricked by the diary Horcrux, either by word or in writing,” Harry said obediently, and smiled at Tom, because it was hard to keep from doing so. “I swear it on my wand.”

The golden light snapped around them the way it had when they were back in the Slytherin common room, and Tom seemed to decide that he could let go of his anger and offense now. He tucked his wand away again, his eyes shrewd. “Did that book tell you how to destroy a Horcrux?”

Harry shook his head. “Only hints and clues. The author seemed to assume that the knowledge was something people would already have if they were reading the book and they didn’t need to say anything about it. ‘The most destructive fire’ and ‘the most destructive poison’ was all it said. So we have to find out what the most dangerous fire spell is, I suppose, or the most dangerous poisonous potion.”

“Hm.” Tom frowned. “I don’t know.” Harry could tell that it annoyed him. “Well, I suppose that it can be our research project for the rest of—however long it takes.” He folded his arms and glared at Harry, as if daring Harry to leave him out of the research process.

Harry wouldn’t have dreamed of it. He nodded. “Of course. Come on, and we can get started. I suppose we can’t actually get into the Restricted Section, but not even Madam Pince pays attention to every single shelf I visit when I’m in the library…”

*

It took concentration, and force. But that certainly wasn’t something that the witch who still thought of herself as Ginny Weasley had ever lacked.

She had to keep reaching, weaving tendrils of her magic through the air to connect with the magic pulsing in Tom’s body. She experienced stabs of irritation as she did it. This certainly would have been easier if Tom had kept writing in the diary, the way he should have been enchanted enough to do.

But still, Ginny’s magic was entwined with his. The diary had fed on it, and had taken control of Tom’s body enough to make him speak the lions’ tongue and release Aurelia. That was a connection that could not be easily or lightly severed.

And, too, Tom was a blood relative, which strengthened the connection. Ginny felt an old, sour satisfaction at the proof that she did have Weasley blood, and wished that Hollis Weasley had left a ghost she might talk to and taunt with her sure knowledge of it.

But she had to save all her strength for the reaching, for the soft and coaxing song that she wove into Tom’s dreams over a period of two months. Since he was suspicious of her now—something she felt without knowing why—it had to be subconscious, even, as he would have rejected a manifestation of her crying about her loneliness and asking him to pick up the diary again.

When she had sung enough to his sleeping mind to make him reveal the memories, she knew fear for the first time since she had been created.

No! They can’t know that I’m a Horcrux!

Ginny calmed down her immediate impulse, though, which was to have Tom sign a message on the wall proclaiming his own death and take himself down into the Chamber of Courage, where Ginny could command Aurelia to kill him. Tom wasn’t alone. Harry Potter knew everything he did, and maybe more, since Tom hadn’t read all of Secrets of the Darkest Art for himself. He had Tom’s brother wand, too. Ginny didn’t know anything about them. It was entirely possible that Harry might manage to track him down or something, given the connection between the wands and the oaths they had sworn to each other.

It would have been simple, comparatively speaking, to possess Tom and make him take steps that he had taken before, although in a sleepwalking state. Ginny could have done it with another month of touching Tom through his dreams. But to make him betray someone Tom considered a friend and had sworn oaths to…

Ginny sighed with irritation. It would probably take until the end of the school year. And that meant she would have to spend all her strength on that goal, instead of having Tom release Aurelia again to kill the animals who were inferior imitations of her glory and people who were inferior members of Ginny’s House. Ginny had so looked forward to having Aurelia kill Minerva McGonagall. How dare the woman call herself a Gryffindor and change into a dirty, scuttling little cat with nothing of a lion’s magnificence.

But no, protecting herself and the secret of the Horcruxes, which was ultimately Aurelia’s secret, too, was more important. And as long as she had Tom place the diary in some obvious location before she had him kill Harry and then himself, there was no saying that someone else wouldn’t pick it up.

It would not be another year before Aurelia roamed free. Ginny swore it to herself, and carefully continued to entwine the tendrils of her magic with Tom’s—a task made easier by his visits to the room where Potter had placed her. The room might protect those outside it from her influence, but not those inside.

*

Harry swallowed and stared at the book in front of him. There was little doubt in his mind that he had found the “most destructive fire” that the Horcrux book hinted at.

This tome, which Harry had picked up off an ordinary Defense books shelf, was adamant that there was no fire spell deadlier or more destructive than Fiendfyre. Then it went on to talk about how to cast it, as if it was a normal kind of spell.

But the note that came after it was the thing that made Harry stare at it with worry and horror stirring in his stomach.

“To cast Fiendfyre tarnishes the soul.”

It then went on to explain exactly how casting Fiendfyre could make the caster care less about other people. Then it could take their memories, give them bad dreams and suicidal impulses, and drive them to the edge of madness, the more often they cast it.

“Those who cast Fiendfyre on a regular basis are the monsters of our waking nightmares.”

Harry closed his eyes and took a deep breath. Then he opened his eyes and read, or reread, really, the last part of the description.

“Fiendfyre has a reputation as a difficult spell to control. In fact, what I have found is that it takes its mood from its caster. The only reason that Fiendfyre so often rages until it consumes everything in the immediate area is because its caster wishes it to rage. They are corrupted enough by their use of it that they no longer desire to hold it back.”

Harry rubbed a shaking hand over his forehead, unsurprised to find that he had actually touched cold sweat.

He couldn’t let Tom see this spell. He was so fascinated by new magic that he’d want to use it. And Tom—

Harry couldn’t let him be hurt that way.

Sure, Tom had already been hurt. His family didn’t seem to care much about him for no reason Harry could discern, except that his parents had wanted a girl. And Tom had a callous attitude towards people already, and he was clever in using his mind to discover blackmail material about other Slytherins.

But Tom was still—whole in a way that Harry wasn’t. He still had a family who would probably be devastated to see anything happen to him, even if they didn’t care about him on a day-to-day basis. He could still be hurt or touched by things like other people laughing at him or someone even suspecting that he had been tricked by a Horcrux.

Harry had grown such a thick skin, had come to see so much darkness and dislike in the world, had distrusted so many people, that he doubted casting Fiendfyre a few times would have any noticeable effect on him.

He’d never really had the impulse to be a hero. He’d faced the Lady Firebrand on the back of Quirrell’s head last year because she had threatened him, and had also implied that she was going to kill Ron when she was done with him. Harry did what he did to protect himself and the few people who were special to him.

Tom was one of those people.

Harry carefully went back to reread the Fiendfyre section again, until he could be sure that he had it memorized. Then he would go and hand the book to Madam Pince with the statement that he was worried about it being out where second-years could find it. He wouldn’t have to act very hard to get her to believe he was shaken and scared.

The book would go into the Restricted Section, and as good as Tom was, he wouldn’t be able to break into it to find the book there.

Harry would make sure that he was the one to cast the Fiendfyre and kill the Lady Firebrand’s Horcrux.

Tom would be safe.