Disclaimer: I do not own Highschool DxD and Harry Potter, all rights are reserved to their owner. I only own my Ocs. I don't have a Beta so if there are mistakes, please tell me where and I will update this chapter.

Chapter 1: A Change of Sorcery (Scenery)

October 10th, 1987. Hogwarts School of Witchcraft and Wizardry.

Albus Dumbeldore is a great many things. A great wizard because of his power (and masterful control over it), a great alchemist because of his apprenticeship with Nicolas Flamel and discovery of a great number of uses for dragon blood. He is considered overall great by all who knew him, this also goes for whoever thinks of him as an enemy.

Yes, Albus Percival Wulfric Brian Dumbledore is a great person. He was currently sitting in his office, thinking of the war that ended six years ago. The war against Tom Marvolo Riddle, a wizard who calls himself 'Lord Voldemort', and other blood purist wizards under his control. Albus couldn't help but think it as ironic. A half-blood orphan wizard leading pure-blood wizards while preaching the power of pure-bloods. He shook his head.

'It is not the time to think about it anymore. Tom is either dead or incapable of fighting against the light for the moment. It is such a shame that most of his Inner-Circle have not been arrested. Such an amount of corruption in the ministry is a shame, but the light is not strong enough to banish it completely.' he sighed and looked out from his office's window. A storm was brewing, and Albus had a feeling that something was going to happen tonight, something powerful. Thunder was heard and lightning formed arcs in the sky. The wind was howling and the full moon was barely visible above the cover of the clouds. It seemed unnaturally bright for Albus.

Suddenly, he saw something peculiar form in the clouds, some sort of vortex was opening in the middle of the tempest. Albus watched curiously as it formed, spanning tens of meters in diameter. Once fully formed, it spat out a human figure and a glint of silver at incredible speeds. Quickly, Albus temporarily disabled the Anti-Apparition wards around the area and swiftly disapparated to the location.

A pop was heard under the howling of the winds and the booms of thunder, Albus appeared, his wand already out. He pointed it sharply to the incoming objects and bellowed.

"Arresto Momentum!" As said earlier, Albus Dumbledore is a great wizard, but the kinetic energy he was trying to stop was plenty so he had to hold his wand in both hands. Concentration visible on his face, with beads of sweat starting to form on his forehead, his power output skyrocketed in a controlled burst for less than a second. The human shape and silver glint both suddenly stopped and dropped to the ground a couple of meters before Albus. He released a breath he was holding, it and the barely formed beads of sweat the only things showing his minimal exertion.

Albus looked in the air, most of the storm seemed to have subsided and the vortex had already closed and disappeared. He looked forward at who or what was spat out. A young man of seemingly seventeen years old with wild blood red hair, Albus was unsure whether the color was because of the young man's wounds or not. He surely wouldn't wait to find out. Next to the young man was what looked like greatsword, a heavy-looking one that was out of its sheath. It had only one edge and was very slightly curved. The blade itself was a shimmering silver with a sky-blue hue. The handle was wrapped in dark red leather with teal rhombus shapes. Both the pommel and the handguard were a gold color, the pommel in the shape of a crackling fire while the handguard had shapes like thunder shooting outward in six directions.

Albus flicked his wand and both the young man and his sword started hovering behind him. He started to walk back to the castle, straight to the Hospital Wing while thinking.

'It is fortunate that all students are asleep and that none today decided to go out of their common room tonight. This young man is gravely injured, but I am sure Poppy won't mind helping him. I wonder how he ended up in that vortex.' He had to stop pondering on the issue for now as he arrived at the Hospital Wing. He directly saw Poppy Pomfrey, the healer of the School, tending to a sleeping student. She turned around as she heard the door open.

"Albus? What can I do for you this late ?" she asked, looking stern and tired. Albus smiled apologetically at the healer.

"I'm sorry for the late visit Poppy, but I found you another patient." He said, gesturing with his wand. The young man hovered to a nearby bed, his sword following to rest next to it.

"I do not recognize him as a student, Albus. Where did you find him?" She asked while starting to cast diagnostic spells on the young man.

"During the storm, an incident happened and this young man appeared with his sword, both shooting out of a vortex in the clouds. I stopped their fall and came directly so you could take care of his injuries. I will need to ask him questions when he is capable to answer to them." She nodded curtly, even if she was somewhat skeptical of the vortex, magic was a strange thing, so she just nodded.

"He is gravely injured, Albus. A lot of broken bones, slashes in multiple places, some very near to his eyes… What sort of battle did he take part in?" she shook her head in bemusement before starting to treat his injuries. "I will take care of him." She assured in a stern voice.

Albus nodded with a soft smile, before glancing curiously at the first sleeping student.

"What happened to young mister Weasley?" he asked in bemusement. Charlie Weasley had two regrowing bones, one arm and leg, he had multiple bruises on his arms and half his hair had disappeared. Poppy glanced at the young man with clear distaste before shaking her head.

"I learned from Miss Nymphadora Tonks that this young man was her friend for the first three years of school here, but at the start of this year he started to join other students that mocked her for her talents or asked her insensitive questions. He went too far this morning and paid the consequences of scorning Miss Tonks." she shook her head again, this time it looked sad.

"Poor girl, ostracised for such a wonderful gift of magic." Albus couldn't help but agree with Poppy. A metamorphmagus is a witch or wizard blessed with a very rare magical talent. The power to change their appearances at will, of course the talent manifests in different degrees. Some can only change their hair or eye color. But Nymphadora Tonks was truly blessed as her gift was in the most powerful form ever seen. She could change hair, eye and skin color, but also her height, bone structure and some of her organs, even if the latter can be quite painful.

"Children are often cruel with someone they don't understand. One can only hope Miss Tonks will be able to find someone that understands her." Poppy nodded in agreement.

"You are right Albus, but I doubt she will find someone of the sort while still in school." Albus thought for a little before answering.

"Life is full of surprises for every one of us, Poppy. And I have a feeling that this young man will be a big surprise for more than one." With this cryptic statement, Albus went back to his office, leaving Poppy to her work.

October 11th 1987, Hospital Wing of Hogwarts

Poppy Pomphrey looked at her newest patient in astonishment. The night Albus put him in her charge, she treated all the slashes on his body, they didn't leave even a little scar. It surprised her but she let it go. She then put his limbs in casts so he would not move during the night. She then went to bed because she was exhausted and trying to heal someone while half asleep is extremely dangerous.

She woke up this morning and cast diagnostic charms on the young man only to find that half of the broken bones were already healed. This shocked her, as she never saw someone heal that fast. She decided to not vanish and regrow the rest of the broken bones in case they were already healing at a fast rate.

For some time next she took care of the Weasley boy. She shook her head once again at his attitude towards Miss Tonks. Such a gift should be celebrated and nurtured, not ostracised. At least the young woman held her head up and didn't let anyone bring her down. A smile came to Poppy's face, one could wonder why Miss Tonks didn't become a Gryffindor with her courage and mischief. But the healer could see why Miss Tonks ended up in her old house. She was a compassionate young woman, very hard working and could cheer up practically everyone, except some Slytherins. Poppy rolled her eyes at the thought of the Slytherins.

When she came to check on the other young man's injuries once again more than 5 hours later, she almost let her jaw fall to the ground. The diagnostic spells told her that most of the broken bones were already completely healed, the only bones that weren't completely healed, only partially, are some bones near the spinal cord. At this rate, the young man would be healed at the end of the day!

?, ?

Originally I was a human, or at least I thought so. A teenage orphan boy going to highschool in France with short dark brown hair and dark brown eyes. An addict to video games, manga, anime, youtube. I was a normal boy without many friends.

Why didn't I have many friends? For multiple reasons. I always was a lone wolf, better alone than with bad company, right? That and I had a hard time trusting people. You see, I always had good instincts. I would sometimes unconsciously ignore someone that gave me a bad feeling, or keep people at arms length because something in my gut told me that I couldn't trust that particular person. At the time, I didn't suspect anything, I just thought that I was in tune with my instincts and emotions, which wasn't exactly false, but it wasn't all. For example, due to analyzing emotions so much, I had trouble truly manifesting mine on my face.

By that I mean that I'm obliged to fake smiles and all my emotions, because otherwise they don't manifest outside my body. Except maybe anger, my eyebrows furrowed a little when I was absolutely furious. I just became an expert at faking emotions on my face to reflect my current emotions. Weird, right?

One day, while going to my highschool, I was killed. I don't know why I protected that person, but my gut didn't tell me that she was a bad person so I didn't keep her at arms length. She was a young woman, with pale white skin, a redheaded woman with blue eyes. Truly, she was beautiful, but I'm not the sort to judge on appearance. She looked lost.

I helped her by giving her indications to where she needed to go, but as she was going to turn at the corner of the street, she was aggressed. I don't know when my body started moving, and at the time I didn't know why I moved so fast. In two to three seconds, I crossed more than 20 meters and punched her assailant. The guy had a black hoodie and black jeans. I couldn't see his face.

When I punched him, he stumbled back before taking a knife out of his back pocket. Now, I did some sport, tennis mostly, but I wasn't exactly bad at self-defense. He tried to stab me in the gut, but I grabbed the wrist holding the knife and twisted it making him lose his grip on the knife. I took the knife before he could take it back, but out of nowhere, he did a roundhouse kick that impacted my chin. I ended up on the ground with the knife three meters behind me.

Apparently, he didn't want to waste any more time, because he took out from his other pocket a gun. He took aim and shot me three times. Twice in the abdomen and the other in my right lung.

I laid there on my back, blood seeping out of my wounds and choking on my own blood. I felt cold. My limbs felt like lead and I couldn't think straight. I soon lost consciousness.

When I had woken up, I was in a space where white was all-encompassing. I don't know where I was, but there was an old man sitting. His eyes opened and he smiled at me.

"Welcome, young man." was the simple greeting. My gut wasn't saying anything about that old man, nothing at all. As if he didn't exist.

"Thanks, I guess. But where is here?" I asked while looking around myself, being careful of keeping the old man in my field of vision.

"You… Are currently unconscious. This is your mindscape, a physical representation of your mind." My eyes narrowed at this. I had trouble believing him, of course, but I shoved my disbelief out of my mind. Because if this was my mind, there were several problems.

"Then, that means there are problems. First, if this is my mind, why is it so empty?" I lifted my left eyebrow in question at the old man. He simply smiled before he started talking.

"Let me tell you a story. It should tell you everything you need to know. Centuries prior, the three great factions. The Angels, Fallen Angels, and Devils had a war. The war of the three great factions. This war was devastating for those three factions, they all lost. The God of the Bible died. Just as the original Four Great Satans, Lucifer, Leviathan, Beelzebub and Asmodeus died. But your story doesn't start after that war. It starts before. An Angel named Crystellia fell in love with a Devil named Manareth Annach. They had a baby, half-angel, and half-devil. Something that shouldn't exist. The baby wouldn't have the weaknesses of any of the two. They were hunted down by the Biblical God and the original Satans, but before they could be killed, they performed a forbidden ritual. The payment for the ritual was both their lives. This ritual sealed most of their baby's power until he would unlock it by himself, and projected the baby far into the future. You are that baby, Jérémy Montague, or should I say Iblis Annach." When he finished, he still had that smile.

I was in shock, Half-Angel, Half-Devil, Iblis Annach? That's not possible! I calmed down quickly.

"That's not possible. I would know if I had powers." he looked at me calmly before answering.

"If you don't trust me, try to do some devil magic. Imagine an effect that you want." I skeptically presented a hand palm up and imagined a fireball appearing. I imagined the power, size, intensity, temperature. I opened my eyes, that I didn't know I had closed, and stared at a baseball-sized fireball. So it was true…

"And if you still don't think I'm telling the truth, think of wings spreading out from your back. Half of them normal angel wings and the other half Bat-like wings." I did as asked, and I felt them, from my back, two pairs of wings. I looked from over my shoulder and saw them. I turned back to the old man.

"Alright, but what's next?"

?, ?

Once I had accepted everything. I went out of my mindscape and continued to live normally. Except that I knew what I was and what my true name was. I trained my magic. Every day of every week for ages. Elemental magic (Lightning, Fire, and Wind were my specialties), Light Magic (From my Angel mom), Language Magic, Transportation (Teleportation is too useful), Look Manipulation, Mind Reading and Protection, Telepathy, Defensive Barriers, and Illusion magic.

After three years I discovered something. My dad was the last of the Annach clan, of the 72 Pillars, and he had a clan ability. He could change his body as he wished. Skin, hair and eye colors, bone structure, organ placements, we could even change sexes! I trained that ability to a maximum and triggered the ultimate form of this ability: Animal Transformation. I could transform into any non-magical animal I wanted.

After five years, my two pairs of wings transformed into three pairs. I didn't need a magic circle to Teleport myself, I just appeared and disappeared in a flash of magic (which means whatever was non-magical couldn't see the flash). For some reason, I hadn't aged physically, and then learned that the life span of a Devil was Ten Thousand years! (Nobody really knows if Angels even have life spans).

After seven years, people from the Underworld sensed my powers and Sirzechs Lucifer himself came to see who I was, what I was doing and why. When he learned who I was, he didn't even bat an eyelash and just commissioned an Evil Piece set from Ajuka Beelzebub, his justification was 'You already surpassed the qualification to become a high-class devil many times over'.

The Fallen and the Church didn't like it and tried hunting me down, I ended up fighting hordes of them in a huge storm and losing consciousness in midair, wishing I was anywhere but here.

October 12th, 1987, Hospital Wing, Hogwarts School of Witchcraft and Wizardry

"Urgh, what kind of barrier did I crash through..?" I complain in a whisper when first coming to.

"Ah, that would be the castle's wards, I'm afraid." A voice answers my whisper from the side. I turn my head to see a very old man wearing robes and a pointed hat. How does he not walk on that beard?

" Wards. That would do it, I suppose." Except that wards shouldn't be able to stop even the lowest of high-class devils, but he doesn't need to know that. Let's see how does my magic fare… Why do I have less than half? I know that I was in a bad state, but still…

"Hello young man," I almost snort, knowing that technically I am more than a thousand years old, while still being truly only 24. "My name is Albus Dumbledore. It is a pleasure to meet you." I nod, a small fake smile pasting itself on my face.

"Likewise, you can call me Iblis, Iblis Annach." He nods, a jovial smile on his wisened face.

"Very well, Iblis. Do you know where you are?" I shake my head, I don't but knowing would be good. I can feel the ambient magic in the air, it is old and there is a lot. The surroundings are thrumming with it, and I can sense a great many magical signatures.

"You are currently in the Hospital Wing of Hogwarts School of Witchcraft and Wizardry in Scotland. I am this school's current headmaster." I nod, so all those signatures must be the students. And this Dumbledore is the Headmaster… he is powerful, for a human at least. He has as much magic as a starting high-class devil.

"Well, I am a long way from home." What I mean by that is that normally, even if the Underworld and Heaven are other dimensions, I can still sense the most powerful members. Where I am in the world doesn't matter, the most powerful I can always sense. I cannot sense them right now. So either I am in another dimension, or the Three Factions disappeared overnight. I can see the old man looking at me sadly.

"Do you know how I ended up here?" He nods sadly before he started to explain.

"Two days ago during the night there was a terrible storm, suddenly in the clouds of that storm a very big vortex appeared and spat you and your sword out." he says, I look to my right and see my odachi Hiraiko propped to the bedside table. With my magic, I place an invisible sound-muffling barrier around the both of us. That way, should someone hear us talking, they would not understand was is being said.

"I see… Well, there's something you should know." I'm not exactly afraid, but I am nervous. Not many Humans would believe that I'm a halfbreed of an angel and a devil. And those that do believe it would most likely try to kill me. Not that they would manage it.

"You see, I'm not Human." I say bluntly, and Dumbledore's eyebrows raise.

"Really?" I can see the surprise in his eyes. He wasn't prepared to hear something of the sort. I nod and deploy my wings, surprising him and making him take a step back.

"I'm half-angel half-devil." Pfft, the face he is making is hilarious. My lips can't help but twitch, but he recovers fast from his surprise.

"Fascinating…Does that mean that God and Satan exist, too?" he mumbles to himself, but I still correct him.

"God existed, as did the Four Great Satans. In my dimension at least." I correct, but I can see the confusion in his eyes.

"Past tense?" I nod.

"In my dimension, the Biblical God died in the same war as the original Four Great Satans." He nods, but I can see that he is a bit disturbed at the conversation before he looks at me sadly.

"So that vortex?" I nod

"Was most likely a bridge crossing the dimensional gap to another dimension, my dimension. I say that because I cannot sense the presence of the most powerful of Heaven and the Underworld, when normally I can sense them from wherever in the world I am." Which is true, I cannot sense them at all. Maybe this world has neither Heaven or Underworld…

"Since I am not capable of opening a vortex, even less across the dimensional gap, it seems that I am forever stranded in this dimension." Genuine sadness entered my voice. I did not have many friends in my world, but I'll still miss some of them. Ah, it could be worse I guess.

"What are you going to do now?" he asks, concern evident in his voice.

"Good question Mr. Dumbledore. What am I going to do with the thousands of years ahead of me?" I mumbled the second part, but if the widening of his eyes and the surprise I can sense, he heard me.

"Are you really going to live that long?" Was that pity I hear? I mean, I know that for him a hundred years is awfully long. But I'm at least half devil.

"Hm? Yes, I am. The life span of a devil is said to be ten thousand years. And we only know that because he died in battle. There isn't a known life span for angels, only that the very first angels were alive ever since their creation." I was incredulous too, when I first heard it. But now that I'm living it? Life already became dull very fast as a human, so I can't imagine how in the Underworld am I going to stay sane.

"That's quite long..." I nod, absurdly long. We stay in silence for a great amount of time, both thinking.

"I may have an idea for the time being." He says after a time. I turned to him curiously, tilting my head to the side and raising an eyebrow.

"This school has stood for close to a thousand years, and it will stand for a long time to come I am sure. Why don't you become its guardian for the time being? Someone to protect the school and all its inhabitants?" That… Actually it sounds like a good idea. In the hundreds of years to come, I might find something to do. But for now, I'll try being the Guardian of the school. And I already know of one threat. But Harry Potter has a destiny to follow and that is the reason why I should let that Basilisk live for the moment. I nod to Dumbledore.

"That is a good idea. For the time being, until I find something to do of my incredibly long life, I will protect this school. And I think I know how to start doing it." My lips form a smile by themselves. Dumbledore is also grinning widely.

"I am glad that you accepted. What do you have in mind?" he looks at me curiously. I decided to explain a little bit bout my father's side of the family.

"In the Underworld, there are 72 Pillars of High-Class Devil noble families. Some of these have special abilities unique to the family. The Annach Clan had the power of Transformation. We can Transform our bodies: hair, eye and skin colors, bone structure, organs, and their placements. We can even change our gender. The Ultimate form of this power is the possibility to become any species of animal at will. I could become a member of your staff in the school?" He looks contemplative for some time, before nodding.

"You could, yes. But what magic can you do?" he looks at me curiously. When I finished telling him all the sorts of magic I had at my disposal, his eyebrows were lost in his hairline in astonishment.

"That is quite the repertoire. Except that you do not use a wand… A teacher wouldn't be a good position for you as you couldn't actually teach all your techniques, could you?" I shake my head in answer. "You couldn't actually become a student for multiple reasons. I doubt using a wand would be useful to you, that and you wouldn't actually learn much. Except maybe Runes, Herbology and Potions? You do not actually need a wand for those subjects. You could just be announced as the guardian of the school and study them on the side." I reflect on his words a bit before nodding, that could work. And perhaps a demonstration of my power to the staff only…

"Your last idea has merit. You could announce me as the first Guardian of the school. Justifying it as a staff position lost to the ages. Citing my power as a reason to become the Guardian." He nods pensively before he looks at me directly in the eyes.

"How much power do you actually have?" I do some calculations. I'm on par with some really strong High-Class Devils, so…

"If I put all my power in a gigantic attack, I could potentially destroy a little country, I think." I think he lost some color. Oh, well.

"That's some terrifying power… And largely enough to appoint you as Guardian to the school. The only problem I see is that you may need some credentials. Like a diploma." I nod thoughtfully. I have mastered Fire, Lightning and Wind magic and have made some great headway to master Earth magic.

"We could tell that I have Mastery over Elemental Magic, Mind Magic, Illusion Magic, Teleportation and Barriers. We wouldn't even be lying." I shrug, technically it isn't a lie. I didn't master ALL of Elemental Magic, but I did master almost four of the five main elements.

"That is extremely impressive Mister Annach." I nod but frown. I don't exactly like my family name.

"Please, call me Iblis."

A/N: Hello, people. I don't actually know why I'm posting this. I just had a burst of inspiration on this during confinement and decided to write this. Tell me if you want me to continue that story. Don't worry, I have not discarded 'Magic, Shinobi and LV', the next chapter is almost finished since two weeks ago. I'm just not in a hurry to finish it. Please tell me if you want more of 'The Hybrid Guardian'. Constructive criticism is greatly appreciated.