So, another story, and I deleted New World, New Life. NWNL might make a comeback if I ever get the motivation to rewrite it, but yeah. Anyway, Harry Potter/Durarara! crossover! I've wanted to do this for a while, and this chapter was sitting unfinished on my laptop. I don't have much planned for this in the way of plot, and it's not that good, so I'm sorry for any inconsistencies and mistakes. This takes place during Prisoner of Azkaban for HP and somewhere between the Saika arc and the Yellow Scarves arc of DRRR, and obviously, I screwed HP canon and changed it so it's set later on in time, and no one has good technology from the 21st century in the 90s.

Also, the title isn't permanent, but it's all I could think of that wasn't shit.

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Izaya Orihara was an odd man, even in his current surroundings—perhaps more so. Yes, the different strangeness made it even more apparent that he was not a normal man, in any sense of the word. Perhaps it was how even though he was clearly not in his depth, he still appeared, on all accounts, to be perfectly at home. Maybe it was how he didn't even try to mask just how different he was to them.

The disgusted whispers coming some of the people in the pub didn't even faze him.

It was probably because, even out of his depth, humankind was Izaya Orihara's speciality. He was only trying to find out if this … community was worth screwing seven times over, whether or not it would be interesting enough to put off Ikebukuro, and for something that apparently began in a pub with a name as bad as the Leaky Cauldron.

Then again, Izaya thought, you should never judge a book by it's cover. If someone with a name that sounded like an air conditioning brand could stir that much up, then he could only guess how interesting this so-called magical community would be. He could learn about Celty's head in a magical place, too, most likely. Oh yes, he realised, this will be so, so interesting.

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"Ah, so you're out looking for a relative?" Tom, the barkeep, queried.

"Yes," Izaya nodded. "I came over from Japan to track them down. So, you'll get me into the Alley, won't you?"

Tom nodded, not questioning the threatening tone of Izaya's voice.

Maybe if Tom had understood that he was essentially letting havoc loose in his society, he would have been more apprehensive.

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Izaya stood outside of Ollivander's, trying to contain his anger.

But those words stuck in his head. "Your magic doesn't have a strong enough reaction to work with a wand."

So Izaya stood outside of Ollivander's until a passing wizard bumped into his side. On purpose.

And then Izaya realised that not being in this society, but still taking part was the best way to understand it. No one realises the truth of a community better than an outsider.

With that in mind, he headed off to the ice cream parlour near him, with money, from the wizard stupid enough to knock into Izaya Orihara on purpose, jangling in his pocket.

In Florean Fortescue's Ice Cream Parlour, Izaya saw a strange wizard. A strange wizard who, Izaya noticed, also saw Izaya. The man was the most eccentric in the shop by a long stretch. He had a beard tucked into his belt, brightly flashing robes with little bunnies dancing around the hem and a large witch's hat that clashed with the entire outfit. At the same time, the old wizard also carried himself with an air of importance unseen in anyone who could be counted as a simple pawn. When this wizard walked over to Izaya's table, the brunette man smirked happily to himself.

"Hello, I haven't seen you before. I am Albus Percival Wulfric Brian Dumbledore." he said in a jovial tone.

"Izaya Orihara." the informant smirked. "I'm new around here."

"Ah. I hope you've found your stay pleasant."

"The people here have a … dislike of my kind. Muggles, I believe you call us." Izaya's tone turned unpleasant, and his slightly different smirk showed exactly how he thought of the ideas these wizards had formed.

Dumbledore seemed oddly put off by this idea. It looked genuine. Izaya was surprised by how someone so clearly old had more modern ideas than the younger generations. "I apologise for the ignorant people's behaviour. They don't understand how a society can survive without magic and not be full of pigs rolling around in the dirt … If I may ask, Izaya, how did you come across our community?"

"I have a magical step-brother. We're not what you call close," Izaya said uninterestedly, "but I know of his magic."

That was, of course a lie. Izaya found out about magic by searching for the odd and unnatural in London. It was kind of hard to not notice entire groups of people disappearing into a closed shop when you were looking for the unusual.

"I see. What do you know of the magical community?"

"Not much more than the fact they are prejudiced and dislike me. Though I would like to find out more. Learning about new things is never bad."

"Yes, I quite agree with you on that one."

"I must ask you, Albus," Izaya leaned in closer and Dumbledore did the same, "do you know anywhere that would have a job for a muggle? I've been thinking of staying in this scene for a while longer; it's a nice change from Tokyo—fresh air, you know?"

Dumbledore was quiet for a very long moment, before he sighed. "There is one thing that might be possible …"

Izaya hid his smirk behind his serious mask as Dumbledore regarded him with trepidation.

"I have a space for a teacher at Hogwarts, and it's a position you could fill. You will need to show me your qualifications first, as well as pass the interview, but there isn't much in the name of competition, to tell the truth …"

Izaya nodded and smiled at Dumbledore. "And what is the job?"

"Our last Muggle Studies professor has quit their job—they felt threatened to do so. I'm afraid I couldn't keep her, but I would ensure that no one would discriminate against you, and if they did, there would be severe consequences."

Izaya smiled. "I would like to apply to be your Muggle Studies, then Albus."

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"I'm almost certain there will be useful things about Dullahan here … Yes … Okay … Goodbye, Shingen-san."

Izaya smirked as he threw the phone down, small, disturbing giggles escaping his throat. His game had got so much more interesting, with so many different ways for him to make it turn out!

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The next time Izaya saw Dumbledore he was being congratulated on his new position, although from what Izaya could tell, as Dumbledore had said, there was practically no competition, especially with his advantage of actually being a muggle.

"So, Izaya," Dumbledore said. "Because you're not so familiar with Hogwarts and magic, and there isn't much longer until term starts, I can arrange for you to go in a little earlier than other teachers normally would, if you'd like."

Izaya smiled. "That sounds excellent."

Things were going well. For Izaya, that is.

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Severus Snape did not like Izaya Orihara.

It was different to how he did not like other teachers. With other teachers, it was a matter of them being annoying, and distrusting of him. In Lupin's case, it was because of Lupin's old friendship with James Potter and Sirius Black.

In Izaya Orihara's case, it was because the man reeked of ulterior motives, betrayal, and backstabbing.

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The first time Snape met Izaya, he was in the library. He needed some hard to obtain potion books, and there Izaya was, in the restricted section, looking at some very questionable books.

"Who are you?" Snape had sneered.

Izaya just smirked annoyingly at him. "Izaya Orihara. And you are?"

His response had tickled a nerve, but Snape ignored that and his question. "The new Muggle Studies professor?"

"Yes." Izaya said. "Who are you?"

"Severus Snape, the Potions Master."

Snape left the room after that. Izaya had left a bad taste in his mouth.

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He did not trust Izaya Orihara at all. He could tell that Dumbledore had made a very bad choice in employing him.

"This is Izaya Orihara," Dumbledore said. "He will be teaching Muggle Studies. He is also a muggle himself, so I believe he can provide a unique perspective on muggle life."

Some conflicted mutters broke out at the last sentence, because, after all, a muggle teaching at Hogwarts was unheard of. Without a doubt, Hogwarts—and Dumbledore—would get a lot of flak, especially from the old and powerful pureblood families.

"Albus, are you sure a muggle can be … safe here?" McGonagall said, just above a whisper.

Izaya's eyes darted in her direction. From what he could tell, she was less powerful than only Dumbledore.

"Minerva, was it?" Izaya butted in. "I know danger, and I also know how to help myself. I'm sure as long as we're all on the same page, we'll all be fine."

Of course, Izaya didn't want everyone on the same page. No, he wanted to be at the top of the ladder, and to pick and choose who rose where, and when someone would fall to the bottom. He wanted to see just how these wizards in their archaic society would react when their entire world fell from below the, and their past became their God, ruling their every decision. He couldn't wait …

McGonagall frowned at Izaya, carefully measuring his face as he schooled his expression flat.

"I'm not entirely sure that will work." she said.

Izaya's lips quirked down, "I come from a very … dangerous part of Japan. I'm used to manoeuvring around loose triggers. Even the muggle world has it's dangers."

The teachers around Izaya considered that and Izaya could tell that he had his battle won. Everyone other than Snape looked reassured, and Snape just looked angry at Izaya's very presence. But, he could play that off as Snape being a racist Slytherin, and no one would have a hard time believing it. Ah, institutionalised hatred was so easy to manipulate.

"Even so, Orihara," Snape began, and Izaya mentally sighed. "That doesn't mean you can defend yourself, nor that you can teach well." His lips curled up in a sneer as he silently challenged Izaya to defend himself.

Izaya's response was dry. "I'm sure you'd be hard-pressed to find someone who understand muggles better than an actual muggle. That aside, my teaching will be up to date, seeing as I come from one of the most technologically advanced places in the world."

He was rewarded with a respected silence from the other teachers, and a glare from Snape.

Dumbledore coughed. "Anyway, I hope you will all be accommodating to Mr Orihara, and will answer any questions he has concerning magic.

The teachers nodded, and Izaya thanked them before he left. "For research." he had said.

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The dullahan, or Gan Ceann, is an unseelie faerie, originally coming from Ireland. A dullahan is often referred to as a headless rider in Muggle folklore, because it carries it's disembodied head in its arm. Dullahan have their own headless horses, which have been rumoured to be able to change form, that pull the dullahan's carriage. Dullahan are feared in both Muggle and magical communities because they bring death with them wherever they go. Unlike the banshee (bean-sidhe), who shrieks before someone dies, the dullahan actually kills people, and can only be tricked by the smartest type of wizard.

The dullahan can see with it's head and has unnaturally good eyesight, able to see for miles and in every direction, and when it sees someone watching it, it has been said to gouge out their eyes with its whip made from a human spine, or throw a bucket of blood on them. It is unsure how the dullahan can see when its head is not attached to its body, but the most popular theory is that it has an invisible head on it's neck, and the one it holds is a fake to trick those wanting to kill it. No one can tell if this is true or not, however, as no one has actually managed to find a dullahan to test this theory on, and not many experts believe it.

Every time a dullahan has been sighted, it has killed someone. They travel to their victims house, and the gates will open, despite the lock and charms holding them closed, then the dullahan will call out their name with an unearthly roar, and kill their victim.

Dullahans can only speak once in their journey, to call out the victims name. The only thing that has been confirmed to stop a dullahan is gold. If one was being chased by a dullahan, the best thing to do would be throw gold in it's path and leave.

It has been said that dullahan serve directly under a god of death, or similar deity.

There have been no reported dullahan sightings in over 100 years.

Izaya sighed quietly, and massaged his temples. So far, his research had left him with more questions than answers. Things like if dullahan saw with their heads, then how the hell could Celty see?

He stirred his coffee, examining the book, and jotting down a note—in Japanese so no one could read it without some effort—in an atempt to understand.

It was so infuriating. All of the potential information waiting for him, and he himself seemed to know more than the magical community.

Well, Izaya thought, it was proof he was better than even wizards and witches. Better than the fantastical, the unimaginable, and the supernatural. He, Izaya Orihara, was truly a God among humans, able to outsmart magical beings with his logic and wit.

He began with his terrible, terrible giggles as he threw his head back in mirth.

Yes, he was in control. He would find out more about dullahan with all of these resources and ensure his ascent to Valhalla.

All he had to do was play his cards right and he would be better than everyone—Dumbledore, McGonagall, Shizuo, the Sonohara girl, Celty, even the Awakasu Association. Once he was done with the magical community, everyone here would be fucked, too.

"Orihara."

At once, Izaya stopped with his laughter, turning around to face the intruder—Snape.

"Yes?" Izaya smirked, masking all the bad intentions previously held in his eyes.

Snape frowned and Izaya could feel pressure in his head, his previous headache returning, and he focussed harder on his poker face.

"What are you doing here?" Snape asked.

Izaya looked pointedly at his book and notes. "I was trying to study something."

"You know that's not what I meant."

"Oh?" Izaya raised an eyebrow. "And what does that tell me about you? Assuming an innocent muggle studies professor has some ulterior motive for teaching. Oh, how you wound me, Severus! I just want to know more about the magical world."

Snape did not look at all impressed. Izaya took that as a win.

"Tell me your real purpose here!" Snape demanded, his eyes flashing with hatred.

Izaya could tell he'd really angered his fellow professor, and mentally noted this, and his other potential anger triggers. "I do need a job if I want to live comfortably. Is that not enough of a reason to teach?"

Apparently, that was something Snape couldn't argue with, and so the hook-nosed professor stormed out of the library, his cape sweeping behind him.

Honestly, if Izaya didn't love all humans, he'd probably pity the man. Clearly, he'd had some things go delightfully wrong in his past.

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That's it for chapter one, kids. How was it? Did I ruin Izaya, or anyone else?

So, big question is, was the bit about dullahan good or nah? I wrote it myself, and tried mixing some not very accurate DRRR stuff, and the stuff on the net, bc the magical doesn't have much on dullahan in this headcanon. I feel like the big bit on dullahan is kinda shit.

Anyway, I have no idea what's going on with this, but I hope I get better.