Nippy bows and disappears.

"I think you may have preyed upon that elf's commitment to the safety of your stupidly named institution."

"The presence in Hogwarts of a portal to another world which will otherwise have to stay open for the next two days while an owl reaches my father is absolutely a security concern."

"Your magic owls aren't even particularly quick, huh."

"They're - owl-paced."

"Owls are not even overland distance fliers ducks would make more sense why owls."

"Maybe there's a mention in a history book somewhere, it's not on my N.E.W.T.s -"

"He's a kind of incurious person."

"That's not fair at all."

"If it were just you you wouldn't even know about electricity not working in Hogwarts."

"To be entirely fair I'm not curious about the owls because owls are interesting or useful, I am curious because they are bizarre, and they probably seem normal to you."

"I think it's not ducks because that'd be less dignified. I bet at some point it was a class thing and then even once everyone was doing it it still had enough of the class-thing feel to it that no one wanted to deviate for practicality."

"Not a bad guess."

"Could be."

And pop that's a houseelf and a man who Cam will definitely recognize. "Timothy, what - Minor -"

"He's from 2179 and there are three different magic systems involved and time freezes when you close the door so close the door we're going to learn everything they knew by 2179 and then I assume Timothy's planning to take over the world."

"- Niblet, can you grab my things -"

The elf vanishes - "Timothy was planning to do that anyway. Are those books from 2179 -"

"Cam, my father, Finis. Father -"

"Nice to meet you," he says distractedly, pulling Minor and eight books into his lap.

"...I'll just amuse myself till somebody has questions, I suppose."

"Do you have an explanation of things loosely tailored to where we're at, I assume the books won't be -"

"Not prepped, no, and I'm not up on your context because my world lacks wizards and I never studied nineteenth century history and even if I had I have spent the last several years participating in a war with an alternate universe version of you against an evil god on a non-Earth."

"...okay. I - really really want to read these books but I guess we should - start with that, actually - uh - go on -"

"Which bit?"

"...gods, alternate universe versions of people, wars, non-Earth -"

"I'm a member of a summonable class of beings typically summoned into a world with an Earth where it's 2179. I got summoned in a fluke happenstance to a world with fifteen large gods, one of whom is extremely evil, and like a million assorted smaller ones, some also evil, and a species I will call Quendi for disambiguating purposes, which includes a family composed of what seem to be as I said alternate universes of you and your kids, who were when I arrived preparing to go from their home planet Valinor to a different planet called Endorë to fight the evil god, and I went along since I have useful magical powers, and there was a war, which was very unpleasant but is now over."

" - okay. Has anyone in 2179 or the alternate planet figured out aging, because if not I still need to get the Philosopher's Stone before we can do anything interesting, time-stop or no -"

"Much improved but not solved; my world there's a disappointing but legitimate afterlife, can't say for yours."

"There's no way to check?"

"I can try conjuring from it but that'll only work if it's not, say, inherently magical in some way."

"We have no reason to expect there's an afterlife except, I guess, that your world has one."

"Mine is not obvious to the living and used to be even less so, for whatever that's worth to you."

"If you can make old notes you might be able to settle all sorts of old rumored lost magics..."

"He can make old notes? I want Flamel's, please."

"Would Flamel want you to have them?" wonders Cam.

"I don't actually care."

"Flamel's the only known creator of the Philosopher's Stone."

"I will make them searchable and look for references thereto and we can stay out of his personal life, then, how about."

"Make them searchable?"

"In 2179 print books are uncommon because it's possible to store information very small and in such a way that nonmagical conveniences can manipulate the content in various ways such as by finding bits of it that say 'Philosopher's Stone' and not 'dear Grandma, for Christmas I want socks'. This will not help if Flamel was in the habit of writing coded letters to Grandma, but it is a reasonable first step." He tucks the works of Flamel into his computer and runs a search. "If he has ever written about the Philosopher's Stone he did so in code or in some inherently magical fashion."

"Frustrating. All right. I should - take one year to learn more science and technology and then go back to that."

"Seems reasonable."

"So - where do I start -"

"Everything in that stack is as introductory as I could easily come up with without being actively misleading."

Nod. "Thank you. And, ah - it is nice to meet you - do you need anything -"

...Shrug.

He hands a book to Minor and opens one and settles in.

He casts something. "Now they can't hear us; they'll cancel it if they want to. Do you want to write up some kind of standard explanation for people who need to know - won't be a long list, but -"

"That's probably a good idea but I'm genuinely not sure how to do it without seeming either defensive or like I'm looking to brag to the kind of person who's impressed by the capacity to destroy planets. Or both."

"I was thinking we'd just not tell people who'd be impressed. What's the worry about seeming defensive, exactly -"

"If I say it would be inappropriate are you just going to argue about something unrelated to whether it would be appropriate or not again?"

"I don't think whether it was right is unrelated to whether it would be appropriate but no, I'm actually just trying to help you come up with an overview so people don't constantly ask questions that awkwardly trip on it."

Sigh. "I would like to put it in enough context that people don't expect me to go about committing random acts of violence, without trying to make assertions about whether I drew the line in the right place, had any business drawing it, etcetera, and I don't know how to do that."

"That makes sense but - I think people in my world might suck more than you are accounting for."

"...and?"

"...and I cannot imagine anyone being at all inclined to debate whether you drew the line in the right place or had any business drawing it? We're still on 'are Muggles people', here."

"So, what, killing fifty five million Elves and assorted deities is no big deal because they didn't have magic sticks?"

"Is going to be a more common reaction than people getting mad at you for it, yes."

"One would have to be not only morally bankrupt but also fairly dense to imagine that magical demons from 2179 sort potential murder victims in this way."

"Oh, I'm not saying they won't be scared, I'm saying it wouldn't even occur to them that there's something to judge you for."

"I suppose I'll take your word for it."

"You also don't really want to be blackmailable and it's sort of an announcement you're blackmailable - no one here can in fact offer that much of a bribe, but -"

"What, 'do as I say or I'll publicize the fact that you singlehandedly caused more civilian deaths than World War Two' - not that they'd make the comparison - I told you it wasn't a secret."

"World war they number them? No, I mean, you made a deal with the evil god wherein he stopped torturing people and you killed people for him, if the magnitude of the 'stopped torturing people' isn't adequately conveyed people will think they can get that deal."

"That is extortion, not blackmail, but you make an excellent point. Possibly also relevant that he was doing so en masse before the notion that anybody he might be able to make this or any similar deal with came along. ...There were only the two, at least by nomenclature."

"Yay. Let's try for zero. Is it relevant that the evil god was doing this long before you arrived, would you not have taken the deal if he'd started in order to get your attention -"

"I would have considered the implications. I did at one point threaten to warn the fourteen not-extremely-evil deities that the deal was on the table if he - fucked with the rules of engagement too much. If they'd been warned it wouldn't have worked."

"Okay. So - not many people need to know at all, but summary for the ones who do that conveys mostly the extreme unusualness of the circumstances."

"Sure."

"Does that accomplish your goals in sharing it?"

"The relevant ones, pretty much."

" - do you prefer I pretend you're okay, or -"

"I prefer not to prompt anyone to consider my emotional state a particularly salient feature of the situation?"

"...okay. I'll try."

"I can produce preferences which aren't that if it's inconvenient."

"There's enough else going on it might be okay. I am not very good at being indifferent to the wellbeing of people around me."

"I don't object in principle to being cheered up, I don't think I forfeited the right to ever be happy again or anything so morbid."

"Oh, good. I think we should vaccinate against everything right now, our population is tiny compared to the populations by the time you finally got around to it -"

"Some of the vaccines would need reengineering, the diseases have probably changed. Malaria's easy because I can just wipe out the carrier species."

"Do you know anyone who can do the reengineering - can any of the Elves or whatever -"

"No, they have totally different biology; there are humans in the world but they're new, like, 'overdeity dropped them pretty much mid-war' new, nobody knows how their immunology works; I know people in Hell who are acquainted with the field, it's possible we could get someone to summon one of them."

"Might be worth it - we should check if summoning works here, but we shouldn't check in Hogwarts, even if it works in general there might be wards against it here."

"Is that a reason not to check, or just a reason to check outside the wards even if it doesn't work inside?"

"It'd probably fail gracefully but I wouldn't completely rule out a bad interaction like 'it lets summoning through but objects to bindings'."

"Ah. Yeah, immunologists I met in medical school are not the most dangerous class of demon by a long shot but still."

"Are there particularly dangerous classes of demon -"

"I don't mean that in the sense of there being different kinds, just different personalities."

"Ah. Anyway, we can check off the grounds - and should soon, that rather changes the best way to fix things up, if we can summon people -"

"I can make it fast, I can make most of a safe circle and a human can fill it in. Do you know any Muggles in case they can do it and wizards can't?"

"It'd be a statute violation, alerting a Muggle to magic even if it's not our kind -"

"That's weird that the Statute is worded that way. Anyway, they don't need to know what they're doing, we can have most of the circle on the other side of a wall."

"That works? In that case yes, I could find someone."

"It is entirely possible to accidentally summon or I wouldn't have appeared when an Elf kid drew on the floor."

"I mean, the wall doesn't disrupt it or something. - if the Elf kid hears about what happened would he - be upset -"

"I dropped a black hole on his home planet what do you think. He doesn't know yet because if he dismisses me I won't be able to put everybody back."

"You have control over his means of finding out?"

"Before I waded into the war I made him and his family and some other families a planet in the middle of intergalactic space where they'd be safe, because if he died I'd be dismissed, too."

"Okay but if they summon someone to ask for the news -"

"Their most recent information suggests that the fourteen dead gods were alarmed that I had been summoned and made it impossible to repeat the feat."

"Okay. I'll think how to find a Muggle to help us with the summoning test."