Disclaimer: This is a work of fanfiction based on the Harry Potter series by J. K. Rowling. No undue claim nor any material profit is expected or intended.

Ivory Tower
by Andrea13 and PersephoneKore

Well, this was a pretty mess.

Helga Hufflepuff surveyed the beach and its strange, spiraling white tower. It was definitely Rowena Ravenclaw's. There weren't likely to be two like that, and the location matched the description the other witch's brother had given when he hired her.

The tower, ivory-white and impractically narrow, strangely ridged but apparently all of a piece, winding up into the air to a point. A blue banner with an eagle on it hung from the windows, too high to reach -- Ravenclaw's device, in colors only magic could have held long against the elements.

he only problem was that one of the few bands of wizard-Vikings willing to use magic in warfare had beaten her there.

Helga huffed and kicked at the sand as she studied the scene. "This was supposed to be an easy assignment," she muttered. Just protect one witch too absorbed in her studies to pay attention to the rest of the world. How difficult could it be? Bah. The witch would have to have a place so distinctive -- and attractive -- to raiders.

At least she had a few distinct advantages. For one thing, the raiders didn't know she was there. She was Disillusioned and had arrived unnoticed, giving her the element of surprise, and she didn't have a bad chance of being better trained. It was, she understood, rather challenging to become expert in battle spells when most of your people, including some wizards, considered magic to be women's business and war-magic to be no ones at all.

Not impossible. But challenging.

Helga checked her weapons -- the tower, however fragile it looked, didn't look likely to topple over or break open in the next few minutes -- and gave consideration to setting the boats on fire. Invisible flames could destroy them unnoticed, unless there were spells set to sound the alarm. But she didn't really want them trapped here; she'd just as soon they go away.

So she fired the boats with showy, colorful flames, and as she'd hoped, some of the raiders were diverted to rescuing the longboats.

That left the others, who'd fallen together in defensive formation and were scanning the beach around them warily. They were seasoned enough to know fire didn't just appear out of nowhere, and it was better to be prepared even if it did turn out to be merely accident.

Helga cupped her hands together and whispered to the wind, turning it loose to shoot out like an arrow and whip the sand around the raiders into a stinging assault.

She was surprised and a little impressed that they had sense enough not to yell. While they tried to quell the sandstorm, she sprinted up the beach, past them, and muttered the unlocking spell Rowena's brother had given her for the tower. The door appeared as a low arch just off to her left; Helga swore (perhaps somewhat unreasonably) at her absent employer for not being more precise than "on the far side from the water" and ducked inside, starting up the steps and casting the restoration spell behind her without looking back. The door slammed shut.

Rowena clearly hadn't designed this place with defensibility in mind, though Helga supposed there could be worse places. At least there was only the one entrance (that she knew of) and the terrain around was flat, providing no hiding places to the attackers. But she had no idea how sturdy the tower would be. According to Lord Ravenclaw, it was actually a horn. A narwhal horn, to be exact, that had been enlarged by magic. Whoever would choose to live in a place like that... Helga shook her head and returning her attention to the stairs. There was a small landing ahead, and a door.

The door, to her surprise and concern, was unlocked and opened easily under her hand. The sight inside just left her gaping and speechless.

But only briefly. Helga strode toward the witch in tucked-up blue robes and seized her shoulder, which finally caused her to turn away from fascinated examination of a giant egg. "Hello, I'm your new bodyguard. Did you by any chance notice," Helga said between her teeth, "that your tower is under attack?"

Rowena blinked at her. "Oh, hello! Robert didn't tell me he was sending visitors. Or at least I don't think he did. I just got this today." She gestured at the egg, turning back to it and running a hand fondly along the shell. "Isn't it gorgeous? I've never had a chance to study a live one before!"

Helga stared at her in disbelief. "A live what?" were the first words out of her mouth. Then she shook her head violently. Maybe whatever the other witch had was contagious. "Never mind that. There are raiders outside your--"

Rowena aimed a wand past her with a thoughtful expression and pronounced an incantation Helga had never heard before. There was a strangled "Urmk."

Helga whirled around just in time to see one of the Vikings fall over on the floor. Her mouth fell open and she eyed the other witch with more respect. Rowena, for her part, had put her wand away and gone back to examining her egg. Helga poked her head out the door warily to see if she'd just been followed by one raider or if they'd managed to break into the tower somehow. "Look, Rowena, your tower is surrounded. Do you have any defenses set up I can work with?" She sighed. "Or at least a window to look out so I can see what I'm aiming at?"

Rowena gave no sign of having heard her. Helga counted to nineteen and repeated her question.

"The tower's defended quite well, really," Rowena said at last, "as long as the door is shut. I take it Robert gave you the key?"

"Yes." Helga tried to remember to stop grinding her teeth. "Apparently he doesn't think you're as well defended as you think, or he wouldn't have hired me."

"He ought to know the tower's safe. I locked him out of it once. I don't usually, of course." Rowena sighed, gave the egg an affectionate caress, and went to tap one wall with her wand. A triangular window appeared, leaning sideways as if to follow the spiral of the narwhal horn. Rowena peered out. "He's probably more concerned about when I leave."

"He said I was to keep you safe at all times, and I don't consider you particularly safe when there are Vikings attacking your tower!"

"But I was fine," Rowena said reasonably. "I hadn't even noticed."

Throwing things, Helga told herself, would not qualify as keeping Rowena safe. ...Well, maybe if she didn't throw anything at Rowena. She sighed. "You might want to step away from the window, my lady. I'll take care of it."

"They can't see the window. It's only one way."

"Better still."

"There's really no reason to be worried," Rowena said lightly, looking out the window for a moment longer before shrugging and moving away. "They'll go away eventually, I'm sure."

Helga looked over at her in disbelief. "If driven off, yes."

"They could just get bored."

"They're not going to get bored when they have a fancy tower right in front of them no doubt full of all sorts of treasure!"

"They will when they realize they can't get in."

Helga put a hand briefly over her eyes. "Can I get spells out? Because if they get frustrated enough without taking any real harm, they will start digging, and unless your tower is not actually sitting on or in the ground, it will eventually fall down."

Rowena was back at her egg now, and barely spared her new bodyguard enough attention to reply. "Of course you can get spells out. It would be a pretty silly window if you couldn't."

"Well, you appear to have rather limited interest in the outside world..." There was no obvious way to open the window, so Helga aimed a curse through the smooth, not-quite-glasslike surface and was relieved to see it strike down at the remaining raiders. She glanced over her shoulder at Rowena and the felled raider just inside the doorway. "Are you planning to do anything in particular with him?"

"I thought we could have dinner in an hour or so."

"...With the raider!"

Rowena looked up and blinked at the other witch's tone. "He looks hungry, don't you think?"

"Did you miss the part where he was planning to rob, rape, and kill you?"

"That doesn't excuse being rude." Rowena shrugged. "If you feel so strongly, you can do whatever you like with him, as long as he doesn't bother my dragon egg." She patted the shell again proprietarily. "And we can still have some dinner. I always get hungry in the afternoons."

Helga gave up on getting any sense out of the Ravenclaw witch and put the remaining raider in a full Body-Bind to make sure he didn't wake up and do anything while she dealt with the rest of his band. "Has it occurred to you," she asked presently, "that most eggs die and rot after a while, if they aren't hatched?"

Rowena blinked at her. "And? This one will hatch; it just hasn't yet. It's not in danger of dying for months at least, as long as it's kept warm."

"Don't most dragon-eggs have to be kept too hot to touch?" Helga aimed another curse out the window, and the raiders gave up and retreated. At least out of view. They could, theoretically, have gone around the other side of the tower.

"I told it not to burn me," Rowena explained absently. "I can hardly evaluate it properly if I can't even touch it."

"...I see." Helga shook her head. "How do I look out the other side of this tower?"

"Tell the window."

"I want to be able to aim out the other side, not just be shown the view," Helga clarified. "At least, I might."

"Whyever would you want to do that? You'll spoil the sand. It's excellent for dragons to nest in."

"Because. There. May. Still. Be. Raiders."

"I told you, the tower is quite well defended. You worry too much."

Helga paused, then tried, "Suppose they spoil the sand?"

Rowena looked up, her eyes flashing in outrage. "They wouldn't! Do you know how hard I've worked to get the habitat exactly right?"

"No," Helga said flatly. "I have absolutely no idea. I didn't even realize you had, as I was under the impression that dragons nested in caves and that everyone had more sense than to want to live next to a brooding one. I am quite sure that none of the raiders have any more idea than I did moments ago that you have made any effort at all or that you'd object to having your beach a less optimal habitat for dragons, nor would they care."

"Dragons live in caves, but for nesting, they need hot sand. And HOW am I supposed to study the reproductive cycles of dragons if I can't study a brooding one? Or the nest? Or the eggs?" Rowena threw up her hands in exasperation. "And then THEY come in here messing up my lovely sand, and YOU come asking silly questions, and no one will let me STUDY!"

The woman was mad. Helga stared at her and thought that the smart thing to do would be to check for raiders, then make her way right back to Rowena's brother and give him a refund for services not rendered. He could even have the one band of raiders for free, as his sister clearly regarded them as trivial. Except possibly on behalf of the dragons.

But she had agreed to do the job. Even if it was starting to look a great deal harder than it had originally sounded -- and not just because of the types of hazards involved.

"If I may ask, my lady," Helga said, "how long a siege could you withstand in here? Or do you know how well supplied you are at the moment?"

"I'm not going to withstand a seige if it means they're out there spoiling my lovely sand! I'm going to go tell them to leave me alone!"

"...I sincerely hope that by 'tell' you mean 'curse very fast, very effectively, with a broad range.'"

"I'm sure they'll listen to reason."

"Are you mad?"

"Reason," Rowena amended sweetly, "backed up with a wand."

"That does sound rather more likely."

"So glad you approve."

"I realize you aren't interested in my approval," Helga snapped, "but I didn't particularly fancy the possibility of having to tell your brother you'd got yourself killed going to reason with a band of Vikings." She glanced out the window. "Though if any are still here, they're stuck. The boats are leaving."

"Good. They'll leave my sands in peace now. And I told you, Robert worries far too much!"

"If you make a habit of trying to lure dragons to your home and expecting raiders who'd happily kill for a tiny fragment of this tower to get bored and go away, I don't blame him."

"They left, didn't they?"

"After I demonstrated that I could damage them from the tower faster than they were making progress getting inside, yes."

"There you have it, then." Rowena turned back to her egg, then frowned. "I should go check the sands."

"And if I hadn't arrived," Helga said in exasperation, "how long would it have taken you to notice they were fouling your precious sands?"

"My alarms would have gone off if they started to do damage."

"To the sand?"

"To the habitat."

"Oh. Well. In that case, why bother checking?"

"To make sure."

"I... see."

"Excellent." Rowena crossed the room, opened the door, and started down the stairs.

Helga followed. "If I may ask again, how long could you hold against a siege in here?"

"I don't know. I've never had to." Rowena brightened slightly as she bounded down the steps. "There's something to figure out! I'd have to work out how much I eat, and how much storage there is, and what I usually keep on hand -- well, and it would be different if you're here. ARE you going to stay, or should I leave you out of the calculations?"

"Your brother hired me."

"All right, then. How much do you eat?"

Helga shrugged. "A bowl of porridge and ale twice a day will do; less if I must, cheese and fruit and flesh if I can find it."

Rowena sighed. "You're being vague."

"I'm being flexible. Estimate a bit less than you'd normally eat, I suppose, and double it; eating lightly is wise when supplies are limited, but growing too weak to fight at all isn't. And it's better to overestimate than underestimate how much food you'll need."

"Hm. Then I'd say a month. Well, 32 days, really."

Helga blinked. "I thought you said you'd have to work out all those things first."

"I did. I didn't say it would take long." Rowena pointed her wand at the wall so the door appeared, then stepped blithely outside.

"I suppose if you're expecting dragons to nest nearby, it would be wise to make sure you wouldn't have to leave often."

"Well, I don't like taking time away from my studies to go for supplies."

"...How often do you leave, generally?"

"When I have to. Not often."

"Don't you find that rather dull?"

"Of course not. I bring the interesting things back here."

"...I gather you don't find people particularly interesting."

"Most people aren't particularly interested in what I do."

"What DO you do? Besides study brooding dragons?" And nearly get yourself killed, Helga added with a mental grimace. No wonder Lord Ravenclaw had been trying to hire someone!

"I study all sorts of things. Dragons are fascinating. So are numbers."

Helga blinked. "Numbers? What's so fascinating about numbers?"

Rowena turned to stare at her, then sighed and returned to examining the sand. "Well, there. You see what I mean."

"I didn't say I wasn't interested, just that I don't understand. I wouldn't have bothered asking if I wasn't interested. I suppose I can see something interesting about numbers. I like numbers when I'm getting paid, after all." Helga was still scanning the beach warily, not quite trusting the convenient withdrawal of the Vikings.

"You can describe a lot more things than money with numbers. All kinds of things about the world. I'm inventing a new branch of mathematics to describe how things behave with magic applied to them. My brother insists on calling it Arithmancy even though that's really a branch of Divination. I mean, you can predict the results of a spell with my method -- or you should be able to once I've worked it out more fully -- but I don't think it properly falls under Divination. It certainly isn't wholly under Divination. Perhaps Divination should be under it?"

"Er..." This was, Helga reflected, wholly out of her depth. "I wouldn't know about that. I don't trust much to Divination. I prefer things you can touch, solid. My specialty's war magic, which is why your brother hired me."

"Dragons," Rowena said, sounding hopeful, "are very solid."

"Yes, they are. But I'm afraid I've only dealt with one when a village hired me to get rid of one that had been eating their sheep."

"Oh... you've killed them?"

"They are dangerous, you know. Well, maybe you don't..."

"They aren't dangerous when you know how to handle yourself, but I suppose to a village." Rowena sighed. "Well, it's still a shame. But the sands look fine. Why don't we go in and have our dinner now? I forget, when I get wrapped up in my egg, and you've been traveling."

"They hunt livestock and people, and most people's homes are rather more flammable than yours." Helga looked out over the beach and the ocean, eyes narrowed -- she could still see the longboats in the distance, though they did appear to be on their way off. She ought to be pleasant. Rowena was pleasant and welcoming, even if she might be mad. Helga wasn't entirely sure of the Ravenclaw witch's motivation -- after all, she'd proposed eating and drinking with the raider as well -- but still. "Do you spoil if you take too long to hatch?" Helga asked a bit whimsically, following Rowena as she started back up the stairs.

Rowena turned her head back and smiled. "No, but I get very grumpy if I haven't eaten recently. Or so Robert claims. I think he just gets more annoying then."

"I've found that most people who aren't used to having to go hungry get grumpy when they're introduced to it. It sounds as if you do it moderately often, but your brother still might have a point."

Rowena shrugged. "I think he's oversensitive, but he's never been very good at dealing with me. That's why you're here, after all."

"Er, is it? I was under the impression you needed a bodyguard, and I must say, between Vikings and dragons, it's starting to look like a more challenging job than I anticipated."

"He thinks I need a bodyguard because he's not very good at dealing with me. I do fine on my own."

Helga regarded her dubiously. "Are you sure?"

"I'm more competent than you or he seems to think." Rowena threw her door open and stepped back into her study; when Helga joined her, she was leaning with interest over the raider and poking at his eyelids.

"Still immobilized and unconscious," Rowena said happily. "My calculations are holding up nicely so far, though I confess I put a bit more power into the spell than I estimated as the standard."

"Wait a moment," Helga said, a slow chill going down her back. "Had you never done that spell before?"

"Well, I didn't have much call to actually do it, but I'd worked out the theory quite thoroughly, I assure you."

"And you chose that time to experiment?" Helga shook her head, incredulous. But then... it hadn't been so foolish as all that; the spell had been untested, but Rowena's aim was clearly well-practiced, and Helga would have cast a curse of her own if Rowena's had failed. "I suppose it wasn't so bad a choice after all," she admitted after a moment, "and with results like that, I think perhaps I could like this mathematical system of yours."

Rowena beamed. "It really is a wonderful system. I think everyone will use it in the future. Once I get all the quirks worked out, of course. Although you seem to do quite well enough on your own."

"I was taught to fight," Helga said. "So what do you want to do with your raider? Wake him up and feed him, kill him, put enough fear into him to send him home to warn everybody off you and take up farming?"

"Hmm? Oh, I suppose keeping him here isn't the best idea. I was thinking of putting a geas on him to go home without bothering anyone."

"I suppose that could work. They're as decent as anyone at home, mainly."

"Mmm. I'll have to work in a twist so he can defend himself if attacked...although perhaps learning what it's like to have to flee or hide might be good for him."

"If he'll leave his ornaments and most of his weapons behind, he might pass without provoking anyone."

"We'll just have to explain it to him when I wake him up. I'm sure he'll see reason."

"Reason backed up with a wand?" Helga's mouth twitched. "It may have to be shown to him."

"Robert always said I was a good teacher," Rowena said brightly. "He'll see sense."

It took Helga a moment to remember that Robert was in fact the given name of the man who'd hired her. "Speaking of your brother," she said, watching Rowena steep herbs and bring out cheeses, "you don't seem to have been expecting me, but you don't seem too upset about the intrusion either. I'd have expected one or the other."

"Oh, I knew he'd send another one sooner or later. He never learns." Rowena scowled briefly into her cauldron. "And he's the one who claims I'm a good teacher."

"Another one?" Helga raised her eyebrows. "Another... bodyguard? How many have there been, and what happened to them?" She rather hoped they weren't all dead.

"Oh, I don't know. I lost track after a while. Six or seven." Rowena waved a hand vaguely. "They...left."


"I believe they decided they didn't like the contract after all."

"Oh." Well, that was all right then. Completely understandable -- Helga had considered it rather seriously herself. Rowena didn't seem quite the type to have done away with them, and though Helga wouldn't have been wholly surprised if it had turned out they'd been killed in the course of defending her from, say, nesting dragons, Helga thought she might stand a chance of surviving the things Rowena got her into.

"I believe you can take better care of yourself than I thought when I first arrived," she said, "and I believe I'd like to learn some of what you've been doing -- if you can design spells without trying them, and handle yourself safely among dragons. But I've got to say I can see why your brother thinks you don't know interesting from deadly."

"Many things are both," Rowena pointed out, handing Helga an earthenware cup and plate. "Here. Don't worry; it's not one of the nastier-tasting potions. Quite good really."

"Right." Helga raised her eyebrows and tried the herbal brew, then set it down. "I think I'm going to consider you too incautious much of the time," she said bluntly. "Knowing that, would you want me around? Because I think I might like this contract anyway, but I'm not quite so full of myself as to think I can fight you and protect you at once."

Rowena hrmed quietly and took her own cup to sit in a battered but comfortable-looking chair by the window. After a moment, she blinked and flicked her wand. A second chair appeared across from hers. "Sorry. Please sit."

There was another long moment of silence after Helga settled herself in the chair, until Helga began to seriously consider repeating herself, not sure if Rowena even remembered what they'd been talking about. But then Rowena looked at her again and said frankly, "I like you better than the muscle-bound idiots my brother has sent in the past. At least you're not going to try to keep me from doing anything interesting. If I get rid of you, he'll just send someone else worse."

"A ringing endorsement," Helga said, finding herself unexpectedly struggling not to laugh. "I'll decline to be got rid of, then. If nothing else..." She grinned. "This should be an interesting stay."