"No."

"Please?"

"No." Hermione snapped her book shut and frowned at Harry. "It's a waste of time-" Harry opened his mouth but she gave him a warning look. "-and effort when we already have a solution that works." She set her book aside. "And you know it works, or you wouldn't be all right with Ron using it, and you certainly wouldn't be enabling him." She nodded at the Room's window - which didn't normally exist, but did today, because Harry had asked it to create one so he could send Hedwig off with an order for gillyweed; the Weasleys didn't have a lot of money, and it was because of Harry that Ron would need it anyway. It was the very least that he could do.

He shrugged.

"I just don't understand," Hermione sighed. "We've got our solution to the task figured out over a month before it. Obviously there's still work to do to get you and Ron ready, but that takes an enormous amount of pressure off. I thought you'd have been glad to be able to slow down a bit, and have a bit of a break."

Harry grunted. Truthfully, it was nice. A lot of what they'd worked on training for for the first and second tasks would be applicable in the third as well, which meant they were well prepared already - at least compared to where they'd been in their preparation for the others the same length of time away. No one was really stressed yet, and they were all on top of their homework; he'd seen Draco and Ron play chess during the week, and he himself had even been able to escape Fleur long enough yesterday afternoon to go for a fly and a game of three-aside Quidditch with Fred, George, Angelina, Katie, and Alicia.

"You were fine until you found out that Snape-"

"Exactly," Harry said. "I don't want Snape's help."

"Why not?!" Hermione said, exasperated. "Draco trusts Snape. Sirius trusts Snape-"

"I know," Harry snapped. He didn't say he didn't want help from Snape because the last time Snape had helped him it had been with Sectumsempra before Harry went off to face Wormtail. Harry'd never told Hermione that, had never told her what had happened when he'd used it, what he'd done. And this was different, the circumstances were different, and he knew better now than to try anything Snape recommended for the first time when he actually needed it, but still. "I- look, I'm not stupid, if we get to the day before the task and I haven't worked something else out, then I'll use gillyweed, obviously. But if I can work something else out in the meantime-"

"You ought to be researching the lake - working out where you're likely to need to go, and what other creatures live in there," Hermione said. "Or you ought to be practicing spells underwater." Harry waved a hand at his hair - still damp - because he'd been doing just that since he got back from visiting Vector, while Hermione sat up here working on her History of Magic essay.

"You know what else is an underwater spell..." Harry gave her a hopeful look. Hermione tipped her head back with a huff.

"If you're going to say the bubblehead charm…"

"How'd you know?" Hermione gave him a withering look.

"It's not only unnecessary," Hermione said, with barely-there patience. "It's also ridiculously complicated - I'm not even sure where to start."

"Think of it as a puzzle, then - a challenge."

"We've all got plenty of other challenges to deal with at the moment," Hermione said wryly. "I'm not sure I'd willingly take on another one. And if I did, I'm not sure it'd be this one; I've never really had much desire to breathe underwater at depth, and if I did, I think I'd just opt to give scuba diving a go."

"You're not even a bit curious about it?"

"I don't think I understand it well enough to be," Hermione said. She waved a hand at the parchment on the coffee table, which held a mix of Harry's and Vector's writing - Harry's, surprisingly enough, the neater of the two.

"You're the brightest witch in our year," Harry said, and was disappointed that Hermione looked more unimpressed than she did flattered, though her scent was pleased. "If anyone could figure it out-"

"No," she said. "So stop asking." She stood and smiled slightly at the look on his face. "I'm not leaving because of you - although you'd deserve it." Harry grinned. "I said I'd meet Viktor before lunch. You're welcome to come with me."

"Thanks," Harry said, "but I'll probably just make a kitchen run in a bit. I've got stuff to work on here." It was true, but it also meant he wouldn't have to see Fleur until dinner. Hermione smiled slightly, like she knew what he was thinking, then bent to tidy her books and parchment into a neater pile on the Room's large coffee table.

"I'll check your working," she said after a moment, sighing. It took Harry a moment to realise what she was talking about, but when he did, he felt his expression brighten. "Only once you're done, though," she warned, turning away from him to head along the bookshelf-lined walkway to the Room's door. "And I don't want to hear a word about it between now and then, unless it's you were right, Hermione, this was a waste of time."

He was fairly sure it was an empty offer; not that she wouldn't help him - she definitely would - but more than she probably didn't think it was likely he'd make it to the point where he'd need his working checked. And, maybe he wouldn't; Vector certainly hadn't thought he'd be able to work it out (nor had Snape though Harry didn't much care for Snape's opinion). But that didn't mean he wasn't going to try.

"How about a thank you?" Harry called after her.

He heard her laugh as she shut the door.

Harry pulled the notes he'd made in Vector's office that morning toward himself and looked over them again. She'd given him several formulas labelled Phase One through to Phase Four (and Merlin only knew what phases were). Vector had written them out in her spiky hand, which Harry was grateful for, even if it had probably meant she didn't trust him to copy them down correctly. She'd also made references to a heap of arithmantical principles that she'd said he'd need to understand for background information - two on pressure (one for air and one for water), one on buoyancy, and four relating to gaseous exchange - again, in her writing. In his own hand, Harry'd written down the diagnostic charms he'd need, and drawn arrows to show which ones related to each of the theories and formulas. Last but not least, Vector had given him the name of what was going to be an undoubtedly riveting read; Fundamental Magic: The Precise Spellcaster's Guide to Proper Incantations, Enunciations, and Wand Movements.

Harry sighed and reached for a quill.

When Draco returned to the Room after lunch, he found Potter sitting on the floor, head bowed, and with his forehead pressed against the wood of the coffee table.

"Hi," Potter said, without moving.

"Potter," Draco said. He'd hoped Weasley might have returned by now. Draco'd seen Granger downstairs and had known she wasn't going to be around, and She-Weasley had been at lunch with her roommates. But it was just Potter.

Granger had told him she hadn't managed to talk Potter out of working on the you-know-what (Krum had been in earshot) and that Draco ought to try. Draco didn't think she was giving Potter enough credit; if this was Potter after an hour or two of trying, Potter would talk himself out of it soon enough, if he hadn't already. "This all looks like it's going well." Potter still didn't move, other than to lift a hand and make a rude gesture.

"Don't suppose you want to work on some arithmancy with me?" Potter asked. He twisted his head to the side so he was looking at Draco, at least.

"Not at all," Draco said, but wandered over anyway, curious. Potter lifted his head, and Draco got a look at the book he'd been resting his face on. It was a double page spread - and looked like it continued onto at least a third page - of a combination of complicated sketches and diagrams that - after several long moments of looking at it - seemed to be incredibly pedantic instructions on how to do the correct wand movements for a spell. The bubblehead charm, Draco guessed. "That looks…"

"Yeah," Potter said grimly, and turned the page to show Draco that it did indeed continue on. "Did you know spells have phases?"

"Should I?"

"No," Potter said, rubbing his eyes behind his glasses. "It's a sixth year thing." He waved a hand at another open book. "They can have two to seven, and there's some spell design formula that lets you work out how many a spell should have and if you're doing a variation to a spell-" Potter glowered at the table. "-those variations target different phases, which is what I need to do, eventually." He looked over at Draco, pitiful. "I think my brain might melt."

"Are you looking for sympathy?" Draco asked. "Because you won't be getting any from me."

"Fine," Potter said, mouth twitching. He flipped the wand movements book shut with a thud. "Let's talk about something else then." He cocked his head. "How'd things go with your dad yesterday?"

Draco narrowed his eyes:

"On second thought," he said, "tell me more about spell phases."

"I can't," Potter said, both amused and a bit sour. "I've told you absolutely all I know about it already." Draco snorted, because he knew lies and this was not one. "So…?"

Draco was lucky to have avoided the conversation this long, lucky, and good at avoiding being anywhere that wasn't public with Potter for more than a minute or two at a time.

"It was fine," Draco said, though it hadn't been:

Father had wanted information: Had Draco heard any mention of the Order of the Phoenix over the holidays, and if he had, did Draco happen to know who its members were, or where they had set up their headquarters?

Draco'd said yes to the first but no to the second - and had mentioned Black, the Lupins, McKinnon, Dumbledore and Severus, but no one else. Though it had made Draco feel wretched to name them to Father, he knew, realistically, he was doing them little harm because they were the ones that were already known, because - with Mrs Lupin as the exception - they had all been members of the original Order (which Draco knew from the photograph in Grimmauld's drawing room). Except, perhaps, for Severus, but Father already knew of Severus' involvement. The Weasleys might be suspect but were certainly not confirmed and so Draco wouldn't be the one to announce their involvement if he could help it. Similarly, Draco had not mentioned that Potter had attended the meeting - the Dark Lord didn't need to know about that, lest he try to use Potter's mind to gain access. Severus - who'd been unashamedly eavesdropping with Legillimency - had made his approval known, adding that it was not just Potter who would need to watch out if the Dark Lord learned of it; there'd also be an expectation that Draco would have access to more information and so have more to share.

Not that Father was at all disappointed with what Draco knew now… Over the summer when Draco had announced he'd be a spy for the Dark Lord, Father had not been pleased, only cautiously approving, but he'd been pleased yesterday. Delighted, even.

It was a monstrous reaction, but Draco suspected he was the only one feeling like a monster when the conversation ended.

Even Severus, for all that he was usually so good at reassuring Draco - or, well, maybe not even that, but he was at least good at putting things in perspective - had only given his shoulder a squeeze and told him that he'd done well, which hadn't really been what Draco had been after.

"Fine," Potter repeated slowly, as if testing the word.

"Yes," Draco said, tone clipped. He waited for Potter to press the point, to ask what Father had wanted to talk about, but he didn't:

"I'm sorry," Potter said.

"Why?" Draco said, surprised, and then amused despite himself. "It's not your fault Father's a-"

"No," Potter said, with a lopsided grin. "That's entirely his fault." His amusement faded. "I- I'm just sorry about this year. I- well, you made sure none of us know exactly what's going on-" Potter's eyes flicked to the dragon on the mantel, the one Weasley had put there. "-but you're still one of us, and you're still having a- It's not been an easy year."

"Not for any of us," Draco said, and was guiltily a little glad for it; between the Tournament, and Krum, Potter and Granger had had no shortage of distractions to keep them from paying too much attention to Draco.

"No, but- Ron told me you've been trying not to- that you think I've got enough to worry about, which is why you haven't said anything to me-"

"You do," Draco said and expected a grimace or a sigh from Potter. He was not prepared for Potter's shoulders to slump, for Potter's expression to crumble. "Honestly, Potter, what you're worrying about is trying to stay alive… that's a fairly good excuse to be a little preoccupied." Draco expected a wry smile and again got it wrong:

"No," Potter said. "It's really not." Draco felt a surge of fondness for him, because only Potter could think that his friends' feelings were worth more than his life. "I- you're important too, and you - and Ron and Hermione - do so much for me, but then when you're dealing with stuff, I'm too wrapped up in me to- Usually- Other years, I've- you've…" Potter's shoulders hunched, and Draco was suddenly very aware that in the past, whenever Draco had had issues with his family and their beliefs, it had been Potter he'd sought out to talk things over with, Potter whose home he'd escaped to. Even at the World Cup it had been Potter to whom Draco had mentioned his parents' desire for him to be a Death Eater. Since then though, since the train and the pensieve and the dragons they hadn't discussed anything of the sort. Draco had visited Potter's but stayed at Weasley's, had taken Weasley into his confidence instead (though Potter wasn't aware of that, or at least not the extent of it). And, while it absolutely had to be that way, for all their sakes, it still made Draco feel a bit guilty.

And in the wake of that realisation was another one; that this was the first time they'd really spoken this year about anything important, just the two of them. They'd been alone together - they often were on the way to and from Arithmancy - and they'd had a number of important conversations, but so far the two had been mutually exclusive.

"You deserve better, that's all," Potter said, and Draco shook himself.

"Potter," he said, "I assure you I'd much prefer you were a bit neglectful-" Potter's face fell even further at that word and Draco hid a wince. "-or a bit distracted, than dead." Draco, after all, was only dealing with stuff, as Potter had so eloquently put it, to keep Potter alive and so it'd be rather counterproductive if Potter went and died in the meantime because he was too busy worrying about Draco. "And you're not the only one that's been a bit distracted. I'm guilty too." Potter's expression didn't change. Draco sighed, exasperated. "Fine: if it makes you feel better, you can fuss over me to your heart's content when this is all over-"

"But it's not going to be over," Potter said. "Not until Voldemort's dead. There's always going to be another thing to do, or research, or another duel to have-"

"Then get on with vanquishing him," Draco said, keeping his voice light and expression smooth; inside he was heavy, because Potter was right.

"Why didn't I think of that," Potter said, rolling his eyes. He didn't look any cheerier, but his shoulders had relaxed and Draco knew his mood had lifted all the same. "I- you know if you do want to talk, I'm not ever too busy-"

"Rest assured if there's something I do want to bother you about, a little thing like your Tournament preparation isn't going to deter me."

"Good," Potter said firmly. Draco offered him a small smile.

"For now, though, it'd be nice to not think about things much at all." Draco cast a thought toward the Room and a pack of Exploding Snap cards appeared on the coffee table. "And whether or not you share the sentiment, I think it'd do you some good to do the same."

"I didn't think you liked Exploding Snap much," Potter said, already shuffling his things to make space on the table.

"It's a horrible, noisy, dangerous game where your success is dependent on luck rather than any sort of strategy or talent," Draco agreed. "That makes it a perfect distraction, I'd say." Potter grinned.

And, by the time Weasley joined them half an hour or so later, Draco - despite the blisters on his fingers, and his blackened sleeve, singed eyebrows, and renewed hatred of Exploding Snap - found himself feeling lighter than he had for quite some time.

"Boys shouldn't be in a- Oh, it's you two." Myrtle bobbed in the air, her ghostly shoes almost a whole foot above the ground, purely, Harry thought, because she wanted to be the same height as Ron. This made her a few inches taller than Harry, who was shorter than Ron anyway, but even more so since last week and the twins' work to build gillyweed compartments into his shoe heels. "What do you want?"

Ron made a strange noise and rubbed his nose. Harry suspected the twins had dosed him with something or perhaps hexed him; for the past two weeks he'd been scratching at his face a lot, like he was suddenly mildly allergic to conversations with people - Hermione and teachers in particular.

"My friend Luna says you like to visit the lake," Harry said. "I was wondering what it's like in there."

"That's a strange thing to wonder," Myrtle said suspiciously. "Why do you want to know?"

"Just curious," Harry said. Myrtle's eyes narrowed. She was disconcerting to talk to; Harry had become so accustomed to using his nose to help him navigate conversations, but from Myrtle there was just… nothing. No scent at all, no way to guess what she was really thinking.

"I think you're trying to get information for the Triwizard Tournament," Myrtle said. "Let me guess, you want to know about merfolk?" Harry and Ron exchanged a look.

"How'd you know that?" Ron asked. It was a good question; Ginny avoided Myrtle at all costs, and Harry couldn't really imagine Hermione discussing the task with anyone on a trip to the loo. Maybe it had been Fleur - the only female Champion - but Harry couldn't imagine Fleur having a lot of patience for Myrtle and so suspected she'd use other bathrooms. Perhaps it had been Cho, if Cedric had mentioned it to her… which he might have. Cho was quite good at Arithmancy - it was her favourite subject, she'd told Harry last year - and so maybe Cedric was getting her help with the bubblehead charm.

"I hear things," Myrtle said, cheeks going oddly opaque - the ghostly version of a blush, perhaps? Harry suddenly remembered what Luna had said at the Ball; that Myrtle sometimes spent time in other bathrooms, without their occupants knowing. Harry decided he didn't want to know.

"Okay, brilliant," Harry said. "So you'll help? Where do merfolk live?"

"Is it a town?" Ron asked. "Could you draw us a map?"

"Draw?!" Myrtle said shrilly. And Ron wiped his face on his sleeve, scent impatient. Myrtle thrust a hand through the wall of the nearest cubicle, then through Ron's shoulder making him shiver. "Draw!? Of all the insensitive-"

"Are they right at the bottom of the lake?" Harry asked hastily. "And north, or south, or sort of in the middle? How deep-"

"I never said I was going to tell you anything," Myrtle said sourly. "Why would I? You're not a Hogwarts Champion, you're competing for some other school-"

"Myrtle, I've been here at Hogwarts for four years," Harry said, exasperated. "I'm a Hogwarts student, the whole Walpurgis thing is just Voldemort-" Myrtle shrieked and covered her ears and Harry sighed.

"Why do you care about the name?" Ron asked. "You died before he started calling himself-"

Myrtle gave him a withering look, then let out a wail - that was more angry than sad - and dove into the nearest loo, splashing both Harry and Ron with water.

"That went well," Harry said.

"Worth a shot," Ron said, grimacing as he wiped toilet water off his face with his sleeve. Harry flicked his wand to dry them both - he'd got very good at drying spells in the last few weeks.

"Maybe I'll see if Luna can talk to her-"

"You can try," Ron said, "but you mentioned Luna, so she'd probably be suspicious..." Harry grunted.

"I guess I'll just make it up as I go, then," Harry said. "Or ask Hermione if she can check the library for a book about the lake-"

"Oh no," Ron said.

"What?" Ron pulled a face and scratched his nose.

"I think I already know the book we need," Ron said. "And Hermione's going to be insufferable about it."

"Oh," Harry said, as understanding dawned. "Hogwarts: A History," they said in grim unison.