I don't own any series that might appear in this story. They all belong to their respective owners.

Dimension Xen.

That was the name given to the dimension after being discovered by humans in an alternate universe. After discovering the secret of space travel, and later, dimensional travel, they stumbled upon this particular dimension. A place, while void of any matter, is filled with energy, an infinite amount of it.

A discovery like that was an evolution. An energy source like that was a treasure, and they used it to its full potential. Everything on Earth used it as its main power source, from weapons to even a light pulp, and later… humans.

Humans thought to themselves, "what if we could power ourselves with this energy?" what if a human was able to wield it?

And so, The Agent Program started.

A small chip, designed to harness the power from dimension Xen directly was invented and implanted inside the brains of the chosen individuals. Its purpose was to allow these individuals to power themselves up with Xen Energy. The program ended up being a complete success.

All of the individuals showed feats far beyond any human could accomplish, even if that human was wearing suits to amplify himself, the individuals were still far more powerful. They showed massive strength, speed and durability, the ability to fly at extremely high speeds, skin many times harder than any metal on earth, the ability to project energy blasts of pure Xen Energy with massive destructive capability, and many more.

These individuals were called Agents, and each one of them was given a number. All the Agents were orphaned children at the age of 14 years all. They were trained in combat since the implantment of the chip at the age of 14 up until the age of 18.

The Agents, after finishing their training, are either enrolled into the army, or sent to other dimensions in order to investigate them, return, and then report.

Agent #52, William Miles, is an Agent who has just finished his combat training after reaching the age of 18. He was assigned to investigate another dimension. What he doesn't know is that he's in for a big surprise, because this is a dimension filled with girls that don't make sense, and have boobs that defy gravity.

Of all the places he had to arrive in, it had to be fucking Japan! He fucking hates Japan! He still remembers the first time he went there, all he found was manga, anime, more manga and more anime. That's basically their culture. Anime, manga, and light novels.

He tried watching an anime before. It was okay for the most part, or at least, for the first ten minutes of it. As the show kept going on, the number of girls after him was increasing rapidly! Like… he had about seven confessing their love to him at the same time! And what the hell is up with his dense ass!? He didn't even notice any of the girls expressing their affection!

He's sorry to say that, but with someone with his lifestyle, that was pure garbage and a million light years far from reality. But that wasn't the only thing that made him hate Japan…

It was these fucking cosplays.

Some 'weebs' as they were called, would dress up as their favorite anime character, sacrificing their dignity in the process, and looking stupid on top of that. When he laid his eyes on this girl dressing like a magical girl, he almost arrested her for public indecency.

He later decided to watch more anime, only to find the same clichés one time after the other. The main character is a loser, gets granted an overpowered ass ability cause he's the descendant of an ancient clan or some shit, turns from an outcasted weeb to an absolute chad, all the thots want his dick, he beats the ass of the bad guy, happy ending, end of story.

You remember how he arrived in Japan? Good, because it didn't end here. He was ordered to attend one of their high schools in order to blend in! Being an Agent is cool, but it sucks sometimes. It's still the 21st century in this world, ao he doesn't want to draw any suspicion.

He sure hopes this mission doesn't take long. He already hated it the moment he arrived.

He registered in a high school in a small town named kuoh by the name of Takashi Shiba, or Shiba Takashi in Japanese. Kuoh Academy was the school's name. A former all girls school turned co-ed lately. Reasons are unknown.

Today is his first day of school. He was wearing the boys' school uniform, which consists of a black blazer with white accents over a white, long-sleeved dress shirt with a black ribbon on the collar, matching black pants, and brown dress shoes. He left the blazer open to reveal his shirt. However, he was not wearing the blazer, but wearing a white t-shirt underneath his open dress shirt with the word 'Cyberpunk' written on it. He had a toned built, black hair that was swept back, a handsome face and deeb blue eyes.

Just as he made his way through the gates, he kept hearing this..

"Who's that guy?

"Is he a new transfer student?"

"Damn it! Another pretty boy!?"

"You should die!"

"The males in this school sure are dicks." He thought.

Just don't mind them and their salt. Keep walking.

After a few minutes to reach his class while hearing these weird gossips along the way, he finally reached his distension. He gave a few knocks on the door until he heard a 'come in' from the other side.

Once inside, he wrote his name on the board in Japanese, then introduced himself.

"Hello, my name is Takashi Shiba. Pleased to meet you." he said with a slight bow and a smile. Although he was smiling, he was really struggling to keep it.

"Any of you have any questions?" asked the teacher. One girl raised her hand.

"Takashi-san, you look like a foreigner, but you have a Japanese name. Why is that?"

She just asked something that is easy to answer.

"Well, that's because while my father is Japanese, my mother was an American. She wanted to call me William, but the name William Shiba would sound weird, so they named me Takashi, but I take almost all my looks from my mother." A nice lie. it's not like they studied genetics.

More still had questions but the teacher stopped them.

"Okay, that's enough for now. You can have the seat behind Himejima-san there." the teacher said, pointing towards the seat with his finger.

""Lucky bastard."" That's what all the boys in the class said. He paid them no attention whatsoever. He just made his way to his seat behind that beautiful girl with long black hair and a huge rack, and didn't say a word. Not even looking at her or greeting her.

"This is gonna be a pain in the ass."

He doesn't know half of it.

Break time. Finally. This class was boring as fuck. They're teaching things that for him are considered ancient. The Agent Program wasn't all about combat training, but every Agent would have to study each and every subject, from biology to rocket science, then pass the paper exam with nothing below an "A". Thankfully, the chip implanted inside his brain enhanced his memory and his ability to store information, so it wasn't that hard.

Onto business. He has detected four inhuman life-forms in his class. The red haired girl with a huge bust, that black haired girl with black hair tied in a ponytail with also a huge bust, the glasses wearing black haired girl who also has a huge bust, and the glasses wearing girl with a small bust and short black hair. All of them have a huge bust, except the one with short hair. He really feels bad for her.

Ahem… back on topic.

Their names were Rias Gremory, Akeno Himejima, Tsubaki Shinra, and Souna Shitori. From what he remembers, Gremory was the name of one of the Lesser Keys of Solomon, a demon's name, so that means that she is a demon. This one wasn't really trying to hide it. The other ones have all Japanese normal Japanese names, meaning only two things; either these 'demons' are truly Japanese, or they're using an alias like him. Most likely the second option.

The students here seem to worship Rias and Akeno, calling them the Two Great Ladies of Kuoh. At first he thought this was some kind of spell, but quickly discarded it as the other two didn't get as much attention as them. They still got attention, but not as much as the first two.

During the break time, he detected even more inhuman life-forms. They were all like the four girls in his class, meaning they're all 'demons'. A handsome blonde second year student, a petite white haired first year, that brown haired second year perv who is a member of the perverted trio ( another reason why he discarded the spell option) and each and every member of the Student Council. Rias, Akeno, that blonde boy, the brown haired one with a stupid haircut, and the white haired girl were all a part of the Occult Research Club, meaning that the Student Council and that club were all a cover.

Again, for that red haired lady, she wasn't trying to hide it.

Conclusion: If he wants answers, he will go to Souna Shitori, the Student Council President. Her behavior during class and outside is a sign of intelligence and responsibility. All he needs to do now is go to the student council.

How did he gather that much info in less than one day? Nobody knows.

Calmly walking towards the Student Council room, William, or Agent # 52, or Takashi (you know what? Don't call him that) was more than ready to confront the 'demons'. A few minutes of walking separate him and them.

He finally reached the room, his arm rising calmly to knock.

"Come in"

That's what he hears from the other side. His eyes lay on the Student Council members. The Souna Shitori with Tsubaki Shinra standing beside her. A blue haired tomboyish girl, a girl with long white hair and blue-green eyes, a short girl with brown hair in long twin ponytails and green eyes, a slim girls with long brown hair that ends in two short braids and matching eyes, and a girl with shoulder-length reddish-brown hair and brown eyes.

"You're Takashi Shiba, the new transfer student, correct? Is there anything I can help you with?" The question came from Souna Shitori.

He didn't reply. He just walked towards her and took a seat in front of her, gazing at her with a serious expression. She seemed on edge, as the rest of the members were, and stared back.

"Who, and what are you really, Souna Shitori?" His tone was serious. She widened her eyes, just like the rest of the Student Council.

"I think I should be the one asking you this, Takashi-san. You are the one who came into my territory. I felt something strange the moment you entered the class, but I couldn't tell what it was." she said.

"I believe I asked first, President. I don't suppose that it is you're human. Am I correct?" Japanese honorifics. He hates them; they remind him of those times everyone who was not an Agent called him sir.

"You would be correct, Takashi-san. None of us here are humans. We are Devils." she said.

"I already figured that much. When I noticed you have a similar energy signature to your Devil friend whose name is Gremory, one of the Lesser Keys of Solomon, I assumed that you were Devils. And it looks that I was correct. Then what's your real name then?" so they called themselves Devils instead of Demons? Whatever.

Souna lowered her head and put her palm on her forehead. He also heard her mutter, "I told her to hide her identity! I knew this would happen!"

She brought her head back up. "In that case, my true name is Sona Sitri, hairess of the Sitri clan of the 72 Pillars. Now that I told you who I really am, why don't you tell me who you are, takashi-san?"

He didn't answer. Instead, he pointed to the chess board near her. "How about this? If you defeat me in a game of chess, I answer all your questions. If I beat you, then you answer all of mine."

The shocked faces of the Student Council members were enough evidence for him that Sona is not to be taken lightly in this game. Their faces mean that nobody challenges her often. that, or there's something more.

"I suppose that's fine."

And so the game began. The chess board was set, and the entire place fell into silence. Sona picked the white pieces, while he picked the black ones. She moved her first piece, and he did the same.

This game is getting harder and harder for her as every second passes. She can't read his strategy at all! With every move she makes, he has a counter. His moves seemed random at first, only to appear later that they're not. No wasted moves, no wasted sacrifice, nothing. He already sacrificed a knight and a bishop, only to take away her queen and a rook. She lost her most valuable piece, and it wasn't looking too bright for her.

"H-He's beating the president!" said the blond boy in shock.

"I can't believe it!" said the blue haired tomboyish girl.

"This is not good! If this keeps up.." thought Tsubaki in fear. That's right. If this keeps up and Sona loses, then Takashi will be in for a lot of trouble.

Sona tried keeping her composure, but from the inside, nervousness took over her. William could see it. The movement of her muscles and the drop of sweat coming down from her head. She's not planning on giving. But… this game ends now. With one final move, he only said one thing.

"Checkmate"

The number of mouths hanging in the air was equal to the number of those in the room, even Sona stared at the board, frozen like a statue.

"I won, meaning you'll tell me what I want."

He juiced out the information from her that day.

"That went well. Now what?"

He got all the info he needed from her. The history of the 'Three Fictions', the Great War, the Devil Civil War, the Peerage system. He has to admit, it was similar to the chip inside his brain, but magical. He also learned about the 72 Pillars and Magic.

He hasn't questioned someone that smoothly ever. The last time he had to interrogate someone, he was forced to resort to…ummm... let's just say difficult methods. Of course, he got her word she won't tell anyone about him. And she is someone who can keep a secret.

He still has to report what he heard, but that will need to wait until Sunday. For now he'll just… do anything. He's in the 21st century, so there isn't much he can do. In that time period, a Camaro that looks like it came straight from Cybertron didn't exist, so he can't go for a ride like back home, nor did they have a motorcycle that looked like it came from the same place.

Damn he misses the year 2212.

He's been her for only one week and he already wants to go back. What sucks is that he has to stay here until he receives direct orders to return.

"This really sucks."

He's just gonna walk around. School is finished for today so there's anything more he can do.

A few minutes later.

You know how much he hates Japan?

A lot.

You remember the cosplays? Yes? Good! Because he now saw what no one should ever see!

He fucking saw a man with enough muscle mass to crush an elephant's leg, cosplaying as a magical girl with his buddies! This is a scene he is not going to forget! Fuck!

How did he see such a scene? Call it his shitty luck.

This town is scarier than he ever imagined.

He's lucky he's not staying here forever.

Back to business. From what he learned from Sona, Angels, Devils and Fallen-angels exist, along with some other species like Youkai. He already learnt about Devils. If he wants to learn about Angels, he only needs to go to the Vatican. Youkai are not going to be easy. They most likely wouldn't hide in plain sight like the Devils in his school, so he'll need to find one.

Now the hardest are Fallen-angels. How is he going to find one? He's in a Devil territory, meaning it's highly unlikely that he'll find one here. He was already familiar with the Devils' energy signature, so he can recognize any of them if he ever stumbled upon one, but he still can't recognize anything other than that. Maybe…

Something is wrong.

There's no one around him, and he's sure there were people here. And the sky's colour also changed.

Has he been dragged into a sealed dimension!? Wait…

"I can feel another energy signature!"

He looks upwards, and sees the source. It's a… tall and buxom lady with long, navy blue hair that obscures her right eye. Her attire consisted of a maroon, trench coat-like top with a wide collar, a matching miniskirt, and black heeled shoes. The trench coat top was open at her chest, giving view to her breasts and cleavage.

Neither her breast size, her pretty face, nor her revealing outfit was what picked his interest. No, it was that she had a pair of feathery black wings on her back.

"So you are the one who I was ordered to kill. I will admit you don't look half bad." she said.

He didn't speak, only kept staring. This one had orders to kill him, but he's only been here for only a week, meaning that he has been discovered since he first came.

"Is that so? Then would you mind if I know the name of my killer?"

"A brave one, aren't you? I suppose there's no problem, seeing that you will die in a few seconds. I'm Fallen angel Kalawarner." she said. Wait a minute. Did she just say Fallen angel? Lady luck must be very generous today!

"A Fallen angel you say? Lady Luck must've been on my side today." he said.

"I think I disagree with you!" she conjured a spear in her palm. It was yellow in colour. Was this magic, or pocket dimension technology? Doesn't matter right now. She threw the spear towards him, aiming to stab his abdomen. She needs to work on her throwing strength, because that thing was really slow and he dodged it with ease.

"What!" she thought, shock written all over her face.

"Interesting." he muttered.

"Tch! Don't get too full of yourself, human!" she said, an expression of anger grew on her face. She kept throwing the spears at him, but he kept dodging them. She began getting frustrated, and launched herself for a more direct assault.

"He's a normal human! How am I not able to kill him!?" she thought in her head while attacking him with her spear. The world was going in slow motion from his perspective, dodging all her swings with ease. She has some experience, but not enough. She appears to have not engaged in many battles.

Unfortunately for her, he decided it's time to end this.

She went for his heart, meaning to stab him, but left herself full of openings. He dodged, then grabbed her by the neck, and gave her a head-butt.

Now if he was a normal human, that wouldn't have been enough, but thanks to Xen Energy, he's no longer a normal human. That head-butt was so strong, it almost knocked her unconscious. He still held back, but his hit caused her head to bleed. She was now on the ground, unable to move, and her face bloody.

This is his perfect opportunity.

"Now you only have two options. Either I take the information I want from you by force, which is in no shape of form going to be pretty, or we can act civilized, have a cup of tea, and you tell me what I want, then I'll simply let you go. How's that?" he said.

"And why should I tell you anything, human!? You should be dead! How are you that strong!?" she particularly screamed at him.

"You are in no position to decline. I'll get what I want from you whether you like it or not. So…" h

How lowered himself to her level, making eye contact. Once she looked at his eyes, she panicked! His eyes were blazing with a bright, blue colour, narrowed, and they looked like they could disintegrate her at any moment.

"What's it gonna be?"

Later at William's home.

Will you look at that! Turns out she can act civilized!

After her beat-down, and getting humiliated by a normal human, not knowing how he did it even after he beat her up, William took her to his apartment. It was a fancy one even! They did him a solid here, better than the shit-hole they let him stay in for a week in the middle of nowhere during the second year of his training. Who the fuck leaves a 15 year old kid in a place like that!?

Apparently… they do.

Anyway. Upon arriving at his house via unknown means (at least to kalawarner) to avoid suspicion, because you don't want to see a young man walking with a hot lady, but her face is bloody, she went to wash the blood off her face and clean herself. After a quick shower, she found that her clothes were as clean as ever. Perhaps he washed them, so she put them up again.

She walked to the living room, only to find him sitting on the table, with a cup of tea in his hand and another one opposite of him, waiting for her to come.

She took the seat in front of him, and took a sip of the tea, and it was damn good!

How can tea be so tasty like that!? It's impossible! T-this is amazing!

"Ahem… if you're done being amazed by that, would you start talking?" He cut her off her world of tea amazement, and her cheeks turned a slight shade of pink from embarrassment so she composed herself.

"I want you to tell me everything."

Another information juicing session.

"And you tell me that you wanted to kill me because you thought I had this Sacred Gear, right?"

"We wanted to kill you before you awaken it and become a threat, but it seems you already did."

"I don't have a Sacred Gear."

"...What?"

"I said I don't have a Sacred Gear. I never had one, and I never will."

"But… but how did you defeat me without using one!? A normal human like you can never defeat me with sheer strength alone!"

Because he's from another technologically advanced world and he draws power from a different dimension. "I simply had enough fighting experience and you didn't. Also yes, I defeated you with sheer strength alone."

"How dare you say that I don't have experience in fighting! Do you know how old I am!? Compared to me, you're barely out of your diapers!"

"Do you know how many fights I had in my life? Compared to me, you're still learning how to walk."

Her angered eyes gazed upon his calm ones. He didn't lose his composure, instead, looked at her like he's talking to the stupid member in the family.

He's been interrogating her for how long now? He extracted all the info about the Fallen and the Angels (he thought that as she is a Fallen, that she was an Angel at some point) that she could give. More things he learned is the magic that they use. Unlike devils who use demonic magic that counts on imagination, they use light magic, which is a weakness to Devils.

He also learned about the Grigori, which is the main Fallen organization led by Azazel. He learned that the power of a Fallen, Angel or Devil is measured by the number of wings they have. The more wings they have the more powerful they are. Meaning that this one right here…

She is cannon fodder. But shhh, don't tell her that.

"You're still just a lowly human! But you barely did any effort. You were holding back, weren't you?"

He was. A lot. "I can't tell you that. I can say that you need some training, and I'd recommend you leave this town soon. The two sisters of two of the current Satans run this territory, and you have no hope of defeating a high-class Devil."

"I don't need you to tell me what to do. And don't worry, I'm not going to stay here for long. There's something I have to do first."

If assassinating him meant anything, then it means that whatever she had to do wasn't good. He'll need to investigate this later. But for now, he can finally go to bed. But he'll need to dismiss this one here first.

"Well… I think I have everything I need to know. You're free to go now."

"Hmph… Finally. I thought this would never end. I've been here for over an hour now."

She made her way to the door. He still hasn't left his seat, so she opened it, but before she stepped out, she took one last look at him, still setting and drinking another cup of tea. She closed the door and left.

Abandoned church.

Kalawarner finally returned. She walked inside the church while thinking. She's been thinking like that all the way. Ever since she left that boy's house, she kept thinking about him.

Why didn't he kill her after he beat her? He didn't look down on her like many others, only taking her with him and giving her the opportunity to wash herself. He wasn't interested in her body like many others too, but only wanted information. She thought that after he takes what he wants, he would dispose of her, or even rape her. After seeing his strength, she had no doubt that he could if he wanted to, but he let her go.

This one has a lot of secrets and mysteries, and he doesn't seem to have the slightest intention of telling. She knew that there's no way he could have taken her out like that. He was a human who didn't know about the supernatural until today, so it's either he's just that strong, or he already knew about it.

But even if that second option was right, the questions he asked were coming from someone who didn't know anything about the supernatural, like asking how their magic works, or who's in charge of the Grigori. These were common info that everybody knows about, but he didn't seem to have a single idea.

"You're back. You sure took your time." said the middle-aged-looking man with short black hair and dark blue eyes. His attire consisted of a pale gray trench coat over a white dress shirt with a matching ascot, black pants and shoes, a pair of black gloves, and a black fedora.

"She's probably been sleeping with someone." Mittelt was a girl with blonde hair styled into twin tails and blue eyes[2].She wore a Gothic Lolita attire, which consisted of a black Lolita dress with white frills, a large black bow on the front, and a green jewel embedded on the collar, white thigh-high socks, and black shoes. She also wore a large black bow on top of her hair.

"Very funny Mittelt. At Least my physics can attract men, unlike you."

"What did you say you hag!?" the now named Mittelt, anger boiling in her face, said directly to Kalawarner.

"You heard me you flat-chested loli!"

"Okay you two, that's enough. Don't fight about everything like that." said the middle aged man.

""Shut up, Dohnaseek!"" the two screamed at the only male Fallen, now named Dohnaseek.

"Enough Kalawarner, Mittlet! I don't need you both howling at each other like that every day!" said the attractive young woman with violet eyes and long black hair. She was wearing what looked like an S&M outfit.

"That's none of your concern, Raynare!" said Mittlet.

"Sigh… I don't know what to do with the both of you." she muttered. "Have you killed the boy, Kala?"

Booom! The question of the day. She can't tell them that she got her ass kicked by a human, nor tell them that she spent the rest of the day in his apartment, or she'll never hear the end of it.

Plus… she wants to know how he became that strong. He holds the secret, and if she could manage to make him spell the beans, she could become powerful too. After all, if a human like him could do it, then why can't she?

"Of course. Unlike you, Ray, I managed to get the job done, and don't let Devils screw it."

"You don't have to be a bitch about it. At least this one is dead. Has the nun arrived yet?" Raynare said back.

"Not yet. She'll be arriving tomorrow." said Dohnaseek.

"Prepare for when she comes. We're finally going to get what we need."

Unfortunately, Kalawrner has something else she wants, and it's in the hands of that boy.

He owes her a lot for telling them that he's dead.

"A nun arriving tomorrow huh? I guess this is what she has to do before leaving. I'll need to investigate more about this."

That's right. The tea he made her drink had a small spying device. It allows him to see what she can see, and hear what she hears (not that he's into spying on her doing… specific things).

"Now I know where they're hiding. From what I heard from Sona, Devils are weak against anything that's holy, and that church is the perfect place to hide." he thought.

His line of thought was cut off by the blue communication circle appearing on his left ear. He tapped it with his index finger and heard a voice from the other side.

"Agent 52, William Miles. Do you copy?"

"Affirmative. The communication circle is working properly."

"Good. I heard that you've started school today. How was your first time in a Japanese school?"

"I can't say that I liked it, but I must admit, the teachers are nothing less than top-tiers."

"That's good to hear. So, how is your progress? I don't expect much actually, you've only been there for just a week."

"I have to disagree with that, sir. So far, I've discovered many other species other than humans in only this small town. They all have the appearance of humans, except that they have wing, but they can hide it at any time. I even got into contact with a few of them. I made sure to not reveal anything about us."

"Really? That fast? Do you know the name of their species?"

"Yes. Apparently, every mythology exists in this world, Biblical or what not. I even managed to gather information on the Biblical fictions, which are Devils, Fallen angels and Angels. The ones I got into contact with were a Devil and a Fallen. I also managed to gather information about their societies. I still don't know about the rest of the mythologies."

"...I see. It's not the first time we see a dimension full of mythical creatures like these. But you managed to collect all this information in just one day!? This is the first time it ever happened before!"

"I guess these are the benefits of having them near you. I'll send my report next Sunday in this world calendar."

"I can't wait to read it. If you managed to gather all that in just one day, I wonder how much you'll gather in another few days. Good luck Agent."

"Thanks, commander. Over and out."

And with that, the call ended and the circle disappeared. He can't say he wasn't nervous. Calling the commander directly is no small deal, but he had to appear calm while taking.

He wonders… if he managed to gather enough info, could he get promoted? That would be a dream coming true. He doubts it'll happen that fast, but a man can dream.

With the day finally over, William went to sleep.

So? How was it? Good? Bad? Tell me in the reviews. It's my first fanfic, so just go easy on me. As you could see, humans are going to be the OG's of the story. They are always looked down on for being the weakest race, but they don't know what the human mind can do given enough time and a motivation.

In case you don't know, DxD is a harem genre, meaning the OC must have a harem, but I'm not doing like most writers and cuck Issei and take away his girls. His harem will not include any of his. Maybe I'll include other girls from other franchises, but I don't want to make the harem so large. Maybe 4 of 5 girls, not 12.

By the way, Sona is in NO WAY shape or form going to be in the harem. Why the hell does everyone include her just after one chess game? How is she gonna marry someone she just met? He challenged her to get information out of her and take her word she won't tell anyone about him. Nothing more, nothing less.

Don't expect to see any Author's Notes during the story, they fuck it up like that. They'll be either in the begging or the here.

More about the empire that William serves at will be revealed in future chapters. I'll try to keep the number of the OCs at a minimum to not mess things up. A big number of characters can confuse the reader.

That's everything I have to say. Leave a review, follow the story, and maybe do a favorite, that would be nice of you. Adios!