DISCLAIMER: I OWN NEITHER D. GRAY-MAN NOR HARRY POTTER.

Tyki075: Hello people! How's life?

Allen: Awful, now that you're back.

Tyki075: Fuck you. Welcome to this fanfiction, it's my first D. Gray-man/Harry Potter crossover, and first Harry Potter fanfiction (unless you count Fuck Off Eren, which I don't).

Allen: You're burying yourself with all these fanfictions.

Tyki075: I know, but I just have so many ideas that I want to write down! Plus, I've wanted to write this for a while, I just never got around to it, what with having worry about When Demigods Meet Exorcists, but I just finished that!

Allen: Yeah, and started a sequel.

Tyki075: Shut up, that's not the point.

Allen: Seriously, how many fanfictions do you currently need to update?

Tyki075: Around six or so…

Allen: You're an idiot.

Tyki075: Plus this one.

Allen: *sigh*

Tyki075: Whatever! Also, this is set in the Prisoner of Azkaban. So, I hope you guys like it! Let us set forth!

'Moyashi' = Neah talking in Allen's head

'Moyashi' = Someone's thoughts/memories

"Moyashi" = Neah talking OUTSIDE Allen's head

Chapter One:

"All we have to do is decide what to do with the time that is given to us." – Gandalf

It had been around 250 years since the end of the Holy War, since the third side of the war had defeated the Earl, since the deaths of so many, since one boy was cursed to walk the Earth for all eternity.

Allen Walker sighed as he wandered the streets of the Ark. Ever since the end of the war, he had been a traveler, destroying any Akuma he came across, there were still some left after the fall of the Earl. For the first ten years or so, he hadn't left the Ark, only wanting to mourn his fallen friends. Everyone had died in the war; he had to watch as all his friends were killed, as Lavi was so consumed by rage and grief after Bookman was killed that he ran right into a horde of level fours, never to come out again, as Komui stepped into the line of fire to save Lenalee, as Lenalee herself had cried as she fought to the last, only to be brought down by the Noah Lulubell, as Marie was overpowered by the Twins, as Miranda, lost without Marie as her defense, couldn't hold her own against eight level threes, as Link was stabbed through by Tokusa, his old friend, as Kanda's lotus curse finally consumed him, as Tyki (who had joined the third side with Road) was stabbed through the heart by the Earl's sword while protecting Allen, as Road set off a bomb, sacrificing herself to kill Apocryphos, as the Science Division was left open for attack, all the guards having been killed as well, and they all fell, as the Generals were slowly overpowered, he watched, unable to do anything while locked in battle with the Earl, he was forced to watch until only him and the Earl were left, alone on a bloody battlefield. He finally destroyed the Earl, stabbing him through the chest with his Sword of Exorcism. The last words the Earl uttered were,

"I curse you, Allen Walker, to forever walk this godforsaken world alone, timeless, ageless, as everyone else continues on, slowly forgetting everything you've ever cared about."

Allen had fallen to his knees, screaming in agony at the loss of everyone he had ever loved, pulling at his hair, wanting to just wake up from this horrible nightmare. He stayed there for days, until Neah, the only one left aside from Timcanpy, managed to get him into the Ark, where he stayed for ten short years.

He wandered the world for centuries, watching everything around him change and develop, as the Order and the Holy War slowly became just a lesson taught to students in history. He thirsted for knowledge, learning everything he could about anything he could.

And now, 250 years later, Allen just happened to be walking the streets of London, when he heard the sounds of fighting and shooting.

He quickly went to investigate and found an old man fighting against three level one Akuma left over from the Earl's time.

Now, through Allen's extensive travels and knowledge, he had obviously already found out about the wizarding world, he had spent a year or two watching classes, just learning. He had purchased all the books he could and read them multiply times. His wand was ten inches, made of ebony, with kelpie hair at its core. He even had a bank account at Gringotts, full of Sickles, Galleons, and Knuts.

So when he saw the old man shooting spells out of a wand, he knew he was a wizard. Of course, spells wouldn't work against Akuma so he decided to step in, activating Crown Clown and slicing through the three Akuma in seconds.

The old man stood in shocked silence for a minute before asking, "Who are you?"

Allen smirked, "Just a traveler, looking for a home."

"Well, you saved my life, I owe you some sort of debt." The old man said.

"No, it's fine, I require nothing." Allen shook his head.

"Please, let me repay you!" The man smiled, "Actually, you obviously have some knowledge of magic, and I am in need of a Defense Against the Dark Arts teacher, you're searching for a home, we could solve two problems with one solution."

"Who are you?" Allen asked.

"I am Albus Dumbledore, headmaster of Hogwarts School of Witchcraft and Wizardry." Dumbledore said.

'What do you think, Neah? Should I accept his offer?' Allen asked in his head.

'I think it would be nice for you to settle down for a little bit, plus this sounds fun.' Neah shrugged.

Allen sighed, "I have been a traveler for far too long, I think a change of pace would be nice. I accept your offer. My name is Allen Walker." He held out his hand for Dumbledore to shake.

The old man took the offered hand and smiled, "Nice to meet you, Mr. Walker. Now, would you mind explaining to me what those things were?"

Allen sighed, having already expected this question, "A long time ago, there was a man named the Millennium Earl, he made these things called Akuma. They were made from the sorrow of human's who had lost someone dear. The Earl would promise to bring the loved one back, if the griever would only call out their name, the griever, lost in sorrow, obviously accepted. They would yell out their loved one's name and call their soul back to Earth, the only problem was the soul would be trapped in a metal Akuma skeleton, then forced to kill the griever and wear their skin. Akuma's main job is to kill and evolve. The Noah family, thirteen people with the genes of Noah, worked alongside the Earl, wanting nothing more than the destruction of humanity. An organization called the Black Order was formed to fight against the Earl, Noah, and Akuma using a substance called Innocence, which could only be wielded by a chosen few, they were called Exorcists. The war lasted for so many years, so many people losing their lives. A third side was formed, consisting of both Exorcists and Noah, this side was formed by a man they called God's Clown. Not long after the final battle began. The Earl and his followers fell at the cost of so many lives, both sides were completely demolished. Only one man remained standing on the field of destruction; God's Clown."

"And those things were Akuma?" Dumbledore clarified.

Allen nodded, smiling sadly.

"And you wield Innocence?" Dumbledore asked.

Again, Allen nodded.

"How is that possible if Innocence existed so long ago" Dumbledore questioned.

"How old do you think I am?" Allen asked, cocking his head to the side slightly.

"You can't be more than twenty by the looks of it." Dumbledore said.

Allen laughed, "Looks can be deceiving Albus. You see, I am almost 250 years old."

Dumbledore's eyes widened.

"I may not look it, but I used to be the best clown; following the path laid out to me, always smiling, even if I didn't mean it, always performing, I really was the best performer, no one ever saw through my act, except for one person." Allen had such a sad, far off look in his eyes.

'Che, Moyashi, stop smiling, stop being so fake.'

'My name is Allen, BaKanda! Get it right!'

"You're God's Clown?" Dumbledore said, then he felt a wave of sadness wash over him at the thought of all this man had lost, "I am so sorry."

'Moyashi-chan! Save me! An evil beast is after me!'

'Get your ass back here, Usagi!'

A tear made its way down Allen's cheek, "It's okay, it's not your fault."

'Shounen, I know you're cheating! I just can't figure out how! Someday, I'll find out!'

'Allen, will you ever teach me how to play poker? Tyki~pon refuses to show me.'

'Don't call me that, Road!'

"And you're all alone?" Dumbledore asked.

'Lenalee! No! You can't get married, I love you too much!'

'Nii-san! Stop it!'

"They're all gone now." Allen said.

'Walker! Get back here!'

'Come on, Two-dots, can't Allen just have a little fun once in a while!'

"They have been for a long time." Allen shook his head, trying to rid himself of the memories.

Dumbledore put a hand on the man's shoulder, "I truly am sorry."

"It's okay Albus, I've had over two centuries to mourn." Allen said.

"That doesn't make it any easier to bear." Dumbledore frowned.

"No, I guess it doesn't." Allen chuckled humorlessly.

"Come on, we must be getting back to the school." Dumbledore said, smiling sadly.

Allen nodded.

"Grab my arm." Dumbledore instructed.

"No, it's okay, I can apparate by myself, thank you very much." Allen declined.

"Very well then."

And with that, the two apparated to the school.

0Oo0Oo0Oo0Oo0Oo0Oo

"Welcome to Hogwarts, Professor Walker." Dumbledore said once they were outside the castle.

Allen smiled, "This will certainly be interesting."

(I was going to end it there, but I really wanted to write more, so whatever!)

0Oo0Oo0Oo0Oo0Oo0Oo

The Golden Trio were sitting in the Great Hall, waiting for Dumbledore to arrive, he was unusually late.

"Where do you think he is guys?" Ron asked.

"I don't know, but look, the Defense Against the Dark Arts seat is also empty." Hermione pointed out.

"It's always empty at the beginning of the year, that job is cursed." Ron rolled his eyes.

"Shut up Ronald, that's obviously not true." Hermione scoffed.

"I don't know Hermione, remember all the other teachers?" Harry chimed in.

Hermione was about to reply when the doors to the Great Hall burst in, Dumbledore striding through them.

He soon got to the podium, "I apologize for my lateness, I was dealing with some important matters."

He went on to make the usual announcements that he did every year, then he got to the subject of the new teacher.

"We also have a new Defense Against the Dark Arts teacher. Please welcome, Professor Walker."

The doors opened again, and this time a young man walked through them. His appearance was rather stunning; he had long white hair that was tied up into a ponytail, if let down it would have gone to his waist, he had a red scar running through his left eye, the top going up under his hair so they couldn't see it, he was of average height, if not slightly short, he seemed to be well toned, like he worked out every day, he was wearing tight black paints, a white dress shirt, a red ribbon around his neck, black gloves, and a long tan coat. The most startling thing though was his eyes, they were liquid silver, but held so much sadness, knowledge, and experience, they were eyes that looked too old for the man they belonged to.

The man strode up to the front, then turned around to face the students, "Hello," His voice was soft and melodic, though had an edge to it that told you not to mess with him, "I am Allen Walker, or Professor Walker to you, your new Defense Against the Dark Arts Teacher. I am quite excited to see what you all are capable of, and be prepared, we will not only be working with spells, but also hand-to-hand combat. I look forward to seeing you all in class. Thank you." With that, Allen turned around and made his way to his seat.

A resounding applause filled the air, soon dying down.

The sorting ceremony was quick and slightly boring. Through the entire thing Hermione's eyes were on the new professor, concentration in her features.

"What's wrong, Hermione?" Ron asked, "Already suspicious of our new teacher?"

"There's just something… off about him." Hermione frowned.

"Lighten up Hermione, you don't even know the guy." Ron sighed.

"Oh yeah, because our last two DADA teachers gave us no reason to suspect them." Hermione scoffed.

"She's got a point Ron." Harry shrugged.

"Fine!" Ron relented, "We'll keep an eye on him! Happy?"

"Very." Hermione smirked.

The three looked up when Dumbledore called for their attention, "Let the feast, begin!"

With those words food started appearing on tables, it didn't take long for everyone's attention to be drawn to Professor Walker, who was inhaling the food at an inhuman rate.

"Bloody hell, where does it all go?" Ron asked in awe.

"I think I've lost my appetite." Harry muttered.

0Oo0Oo0Oo0Oo0Oo0Oo

The next day was Allen's first class as a teacher.

'You excited, nephew?' Neah asked, smiling.

'Yeah, I think this will be a very interesting experience!' Allen exclaimed.

Neah chuckled, 'I'm glad to see you interested in something for the first time in a long time.'

'Me too, uncle.' Allen smiled.

Soon the students began arriving, taking their seats. Allen immediately spotted the Golden Trio, who Dumbledore told him to keep an eye on.

"Welcome," Allen said, "As said yesterday, I am Professor Walker. Now, today we'll be focused mainly on just getting to know each other. Does anyone have any questions they want to ask me? When I call on you, please state your name as well as your question."

Basically the entire room had their hands raised.

Allen sighed, "You."

"My name is Ron Weasly. Why is your hair white?" Ron asked.

"Let's just say that I went through some childhood trauma." Allen answered, "You."

"My name is Pansy Parkinson. What is that red line down your face, is it a tattoo?" A Slytherin girl asked.

"It is not a tattoo," Allen said, "I was cursed."

"By who?" The girl asked.

"My father." Allen said simply.

"Why do I get the feeling that these kids are going to be more difficult than the Holy War?" Allen muttered under his breath, so no one could hear.

The class' eyes widened.

"You." Allen continued, ignoring the class' reaction.

"My name is Seamus Finnigan. How old are you?" A Gryffindor boy asked.

"I am twenty-three." Allen said.

'Liar.' Neah commented.

'What am I supposed to say, 'Actually, you know, I lost count, it's somewhere in the two-hundreds, all I know for sure is that I am older than Dumbledore.'? I doubt that would go down well.' Allen sighed.

'Good point.' Neah nodded.

"You're really young! How are you teaching?" Seamus asked, eyes wide.

"Excessive experience." Allen said, "You."

"My name is Harry Potter," Harry waited for the usual reaction he got when he said his name, when he got none he was surprised, but he continued, "That ribbon you hold your hair up with, it looks really tattered, why not get a new one?"

Allen laughed, "What a strange question, Mr. Potter. But it belonged to someone very dear to me, someone who I haven't seen in a long, long time, it's very important to me. Why would you ask a question like that?"

"I don't know, it's just completely different to the rest of your attire, which is more formal, clean, and well taken care of. I guess I was just curious, sorry for prying." Harry said.

Allen had used magic to preserve the ribbon so it wouldn't get destroyed any further after hundreds of years, but he still wore it, all the time.

"It's not problem, Mr. Potter. You." Allen gestured to a snotty looking, platinum-blonde Slytherin.

"My name is Draco Malfoy," The boy sneered, "What is that weird gold thing flying around you? Did you steal a snitch?"

Allen chuckled, "No, nothing like that. This is Timcanpy, he's a golem, my uncle made him, he's been with me for forever really. You."

"My name is Hermione Granger," A bushy-haired Gryffindor said, "I heard you say something about a 'Holy War' what is that?"

Allen smiled, but it was different than the smiles they had seen so far, it was slightly too big to be normal, and held within it traces of insanity. It was dark, and the class could have sworn they had seen his eyes flash gold for a split second, "That is something you should not worry yourself with, Miss Granger."

The class was silent, Hermione staring at the Professor, while he stared back.

Then the bell rang (is there even a bell?).

"Well, class is over. Your homework is to write two to three things about yourself, you'll be sharing them in class tomorrow so I get the chance to know you as well. You're dismissed." Allen said.

The class shuffled out, grumbling about there being homework on the first day.

0Oo0Oo0Oo0Oo0Oo0Oo

"I really don't trust him." Hermione said as soon as they were out of the classroom.

"Yeah, he was sort of strange." Harry muttered.

"At least he was nice," Ron shrugged, "Just don't get on his bad side."

"Why are you so insistent that he is trustworthy?" Hermione asked, whirling around to face Ron.

"Because Dumbledore trusts him, respects him even. We've all seen it, when he looks at Professor Walker he gets this sadness in his eyes, like he can't even begin to imagine the Professor's pain." Ron shrugged, "I trust Dumbledore, that's all."

"True as that may be, there is definitely something going on here. I suggest we look up the Holy War." Hermione decided.

"Really? It's the first day, can't we just be normal for a week or so?" Harry groaned.

"Don't whine, I want to get to the bottom of this. He was obviously trying to hide something involving the Holy War." Hermione scoffed.

0Oo0Oo0Oo0Oo0Oo0Oo

That night the Golden Trio had the Invisibility Cloak out, all three of them hiding under it as they snuck out to the library.

"You know, it's getting progressively harder for all of us to fit under this thing." Ron grumbled, not at all happy about having to do this.

"Shut up Ronald." Hermione said, "Come on, it should be somewhere in H."

They stopped suddenly when they heard a voice.

"Tim, really, you couldn't have recorded the directions when Dumbledore gave us a tour? You know I'm still the best at getting lost. I don't care how many years it's been! No, Neah wasn't paying attention either! Is he ever?"

They seemed to be hearing only half of the conversation, so they peeked around the corner, spotting Professor Walker talking animatedly to the golden thing he had called a 'golem'.

"Who do you think Neah is?" Harry whispered.

"I have no idea." Ron muttered.

They heard Professor Walker sigh, then he began to walk their way, they backed up slowly against the wall and froze, barely even breathing, not wanting to get caught.

Just as they thought they were out of the woods as Professor Walker passed them they heard him say one more thing, "You know, you three should really be in bed. It's rather late isn't it?"

They froze again, not believing that he knew they were there.

Professor Walker chuckled, "Go back to bed, I'm sure whatever you are doing can wait until tomorrow." With that he walked off, turning a corner.

They went to follow him, just to see what he was doing, but he was gone. He had just vanished.

They quickly made their way back to the Gryffindor common room, not wanting to be caught by Professor Walker again.

"Bloody hell, that was terrifying." Ron gasped as soon as they were through the door.

Harry nodded his agreement, "I'm surprised he just let us off with a warning."

"But what was he doing?" Hermione insisted.

"Really Hermione, can't you just leave it alone?" Ron sighed, "He's obviously not evil like you seem to assume, he just let us go! He even sounded amused! He's obviously not a bad guy! I mean, really, just because he doesn't want you snooping around in his past that makes him suddenly a spy or something."

"I just don't see what he's trying to hide!" Hermione exclaimed, throwing her hands up in the air.

"Hermione, I think Ron is right on this one, it's perfectly normal for Professor Walker to not want us to know everything about him, everyone has their secrets." Harry said, walking up to the boys' rooms, "Goodnight, see you tomorrow."

Ron waved at Hermione, then followed Harry.

Hermione sighed as she was left alone, frowning, 'Maybe I am just being ridiculous, Professor Walker has every reason to want to hide some things from his students. I don't know, I just have this feeling that we don't know the whole truth, that there's something big going on here.' Hermione trudged up to her room, deciding to think about it in the morning.

0Oo0Oo0Oo0Oo0Oo0Oo

Allen eventually made it back to his room, closing the door quietly behind him. He leaned against it and let a Noah smile take over his features, a slightly insane laugh escaping his lips.

"Yes, I think this will be very interesting."

End.

Tyki075: Wow, I am so proud of that chapter!

Allen: Why am I so… bat-shit crazy?

Tyki075: You're not, you've just been alone for a long time, you've been bored for over two-hundred years, you've just found your entertainment.

Allen: Oh great.

Tyki075: I promise, Allen isn't evil in this story, just a bit… I don't know… sadistic at times. THIS IS IMPORTANT; I WANT YOUR IMPUT ON THIS ISSUE, I WAS WONDERING IF I SHOULD HAVE SOME OF ALLEN'S FRIENDS REINCARNATE. YOU KNOW, HAVE THEM REMEMBER, JOIN THE CREW, I DON'T KNOW, IT'S JUST AN IDEA. BUT PLEASE, PLEASE, PLEASE TELL ME WHAT YOU WANT! JUST TELL ME INA REVIEW OR SOMETHING, I REALLY NEED HELP WITH THIS DECISION!

Allen: I still can't decide if I'm okay with this story or not… I mean, you did kill everyone I loved… You know what, I think it's pretty fucking obvious. I am so not okay with it, fuck you.

Tyki075: You're so mean to me Alley-chan! Anyways, remember TELL ME WHAT YOU WANT! I'M SERIOUS! Also, I will be adding Lupin to this story, he's just not the DADA teacher, he's sort of essential to the plot, so he has to be here, plus he's one of my favorite characters, I can't just leave him out. Other than that, there's nothing else I have to say! Review, fav, and follow! I hope you guys liked it, I'll try to update soon! Squadala!