Disclaimer: Naruto x Highschool DxD - I own neither
Story Start!

2 years.

For 2 years almost nobody bothered him at all, which sucked because that meant that he had not been rescued for 2 years of being trapped in a world that he had no knowledge of at all. He stayed in put and barely moved from where he had landed, but alas, in the end, nobody had come to bring him back to his home dimension.

The only thing that happened were random people coming to fight him.

He didn't kill them, he just beat them up just enough to make them give on on fighting him, and then he healed them up enough to allow them to escape from him. He had a few women that came to fuck him, but he just turned them away politely, and that usually led to a fight as well, where he turned them away NOT so politely.

"Sorry ladies, but Uzumaki Naruto is not into emotionless fucking... I prefer girls who want to build a life together. This 20... 21 year old man is not cheap, I demand... I'm lonely." Naruto complained as he talked to his reflection in the calm water he was sitting on. Nobody had come to fight, fuck, fuck/fight, or fight/fuck him in weeks, and he didn't want to stray from where he was too far. If a portal opened up, and he wasn't there to walk through it, then there was no telling when another one would open up. "... I'm also getting sick of sea food!" Naruto near a beach, and it was no problem for him to just have Isobu inside of him make fresh water.

He was getting sick and tired of having to stay on a beach and go for sea food.

"Then go do something, nobody is coming at THIS point. Your chakra is too massive for them to not be able to pinpoint the exact dimension you're in. Last time you were separated from Sasuke and Sakura, they opened a portal with Obito right to the dimension you were in... 2 years have passed, they aren't coming." Kurama inside of him spoke up.

Naruto sighed and hung his head.

"... Yeah... they might be dead, in which case... I'm just stuck." Naruto agreed as he laid back.

-3 Weeks Later-

Just because he knew nobody was coming for him, didn't mean he had to move from where he was right away either. Naruto laid against the ground, and when people came to fight him, he accepted the challenge and beat them back. The ground around him was scared by dozens of battles that had been happening more frequently, and some people just kept coming back for more and more punishment.

The white dragon armor kid needed to STOP coming and picking fights, he was lucky as it was to survive the first time when Naruto used his own chakra to stop the kid from exploding. The kid had nearly killed himself by stealing some of his chakra, and the chakra overload had almost caused him to explode.

"Uzumaki Naruto."

"Are you here to try and fight me, or fuck me?" Naruto rubbed the back of his head as he sat up. He was getting more and more freaky visitors, a group of people claiming to be heroes, a group of people claiming to be devils, some freaks with black wings.

A strange kitty girl with an entire black cat theme to her had tried to fight and fuck him, so he kicked her ass twice and sent her on her way. Yet, she came back 3 more times since the first time, and had continued to get her ass kicked. He didn't bother learning the names of anyone who had come to fight him.

"I am here to test you."

A silver haired maid.

Naruto made her sweat when he looked at her, and he just gave her a glare. He sent her a thumbs up, but what he did was a lot more menacing than simply a thumbs up. He charged up his chakra and allowed it to run rampant around his body, causing boulders to lift out of the ground and float. The woman's body was crushed under the pressure and her knees were visibly buckling. The density of his chakra filled the entire area, and she just wasn't powerful enough to really do anything when he gave her his thick, killing intent filled chakra.

"I pass." Naruto stated as he laid back down and relaxed his chakra, lowering his thumbs up.

The maid nodded.

"... Yes... I have been asked to offer you... a job..."

"Not interested in a job, I'm just going to relax. Unless you plan to pay men a LOT of money for this job."

"How does 100,000,000 yen a day sound?" Grayfia offered Naruto.

He looked at her with amusement.

"I have no idea what yen, so I don't know how much you're offering. Clearly, it's a very large amount... but is it large enough for you to hire me?" Naruto asked, since that sounded like a very large amount. He was interested in why it was by the day, but overall, he couldn't care less about a job that paid well, if it was a job he had no interest in doing. "So, you want a person dead... a group of people dead... oh... let me guess, you want me to impregnate a group of powerful women... I'm not interested in any of those things." Naruto had no desire to be used by corrupt people for no personal gain to himself.

"Just do it, you've been bored for 2 years." Kurama told him from inside of his mind.

Naruto just smiled in agreement.

"I will... hear you out though."

"You are being offered the chance to teach a group of young devils combat, over the course of 10 days. They have an important competition coming up, and need all the help they can get." Grayfia simply explained what he was being offered a job to do.

Naruto scratched the back of his head in confusion.

"... That's it?"

"Yes, that is all. The man who wishes to contract you, does not think that this group has a very high chance of winning their competition. He wishes to hire somebody strong enough to train them... but neutral enough to not ask questions." Grayfia had never thought a person would be able to fit the conditions.

1. Powerful
2. Neutral to all sides
3. Unknown to most people
4. Experienced

She could sense his power, and it was a power that had seen countless battles in a short time. Battles that she could hardly imagine for herself. She had never sensed somebody who had a power like him, or had a power as strong as him. She knew his name because the rumors of a guy that had been hanging out at this exact spot for 2 years and had been undefeated by everyone who had challenged him was becoming well known amongst the strongest people of their world.

"Just training a group of brats?" Naruto asked as he stood up, and shook the dirt off himself.

This was interesting to say the least.

"Just training them for up to the number of days I gave you. You can train them from 1 to 10 days, and you may use whatever non-lethal methods you see fit." Grayfia explained how much freedom he would have to train the group.

"Can I cause them pain, and bring them to near-death so long as I heal them?"

"... That is a very worrying statement." Grayfia admitted with a frown. He worded that very accurately, meaning that he had a plan, and he knew that what he was going to do was going to cause a lot of pain and suffering.

"Can I force them to cry, sweat, bleed... and maybe puke?"

"... I think you might not be the correct man for the job." Grayfia was rapidly changing her mind on if this was a good man to pay to tutor the group or not. He was saying things that were very worrying to her on a personal level, and the fact that he had added puke onto the list of things that he was going to do to them just meant that he had expectations.

Very dark ones at that, expectations for levels of suffering that she didn't want to imagine the group going through.

"... they won't die, and I wouldn't dream of causing any permanent physical damage. If all you need is a combat couch, I actually don't see a problem with that." Naruto stated as he started to stretch himself out.

Just teaching some brats combat?

He was a Taijutsu teacher at the Ninja Academy... well... before he got sent on a mission to the moon, and he had been a teacher for a short time, but he had still been a teacher. He had experience teaching, and he actually enjoyed it to some degree. If all he had to do was get some rookies some experience and knowledge, then there was no reason for him to refuse such a generous offer.

"That is oddly specific."

"I can not promise that this training won't leave them with life long mental scars, and honestly, I might be a regular part of their nightmares in the future." Naruto admitted that the training was going to be very harsh.

Harsh, but completely realistic, and not sadistic.

It would just be harsh, hard, and brutal training. The kind of training that could absolutely cram a ton of basics and experience down the throats of the unlucky victims of the training. A kind of training that he himself had recieved on the battlefield many times.

"I, am not amused by-"

Grayfia heard a voice, but before she could see who was speaking, Naruto flashed right by her and punched the speaker in the face with a glowing golden fist. Her eyes widened when a black blur went flying high into the sky, and instantly out of site. Naruto whistled and looked out into the distance, a grin on his face.

"Okay, that one got some distance... I wonder how long it will take her to recover from that one... and how far she is going to go." Naruto grinned as he looked way into the distance. The person he punched had already gone at least halfway across the planet at this point. "I really put some distance on that one... I'm trying to see how far I can punch that goth loli without killing her." Naruto explained.

She was one hell of a durable goth loli, she could take a punch better than anyone who fought him so far. Since he didn't want to kill her, he started to have fun with it. He punched her hard enough to defeat her by knocking her out cold, but not hard enough to kill her. He also made sure to send her flying at an angle so that she would go as far as possible without being sent into space. He was having fun, since she was durable to survive the landing unlike most people he wanted to punch that way.

"What?"

"There is this goth loli that likes to bug me, so I punch her as far away as I can without sending her to space. Last time I punched a full grown man all the way across the moon... so with her smaller body, I want to see how far I can punch her without killing her." Naruto had that limit, he had to punch her just hard enough to knock her out without killing her. That meant he had to limit himself on not going full power, or blowing her head off her shoulders. He had to really aim just perfectly, hit the perfect sweet spot, and then put a spin on it.

"Goth loli... what?"

"Don't know her name, forgot it... but this goth loli hag."

"Goth loli hag?"

"Her true age is way older than what she looks, she's an old lady... but still, kind of cute overall. She talks tough, and she's the strongest fighter I've met so far in this place." Naruto would give compliments where they were due. She was a cutie, though she could do herself a favor and cover up her tiny boobs a little more. She only covered her nippled with black X pasties, and that was it. Her shape of her nipples was visible through them, which meant that other than the color of her nips, she was leaving nothing to the imagination. "She's stubborn, she'll be back, and I'll see how much further I can punch her. Still, I don't really know how far I'm puncing her until she tells me... I can only guess. I just know that she at least goes halfway across the planet... durable goth loli." Naruto extended his hand to Grayfia.

She didn't shake his hand, she just gave him a polite bow.

"Well then, if you will follow me. The sooner we leave, the sooner we can arrive. Wha-!?" Grayfia shouted in actual surprise, her cheeks turning bright red.

Naruto picked her up like a princess.

"Just tell me where to go."

"What do you AAAAAAAH-"

The vanished in less than a blink of an eye, too fast for Grayfia to do anything but scream at the top of her lungs at the shocking speed. She had simply never moved faster in her life, and she never expected to move faster. She watched the ground underneath them vanish, and in another instant, they were running over the ocean. In literal seconds, they had crossed whatever country that they had been on, and were not running over the top of the ocean. It wasn't until they went over the ocean and hit land, and started to cross another continent that she realized that he was crossing land faster than the speeding of lightning itself.

A black blur slammed into the ground next to them as they ran, but they were going so fast that Grayfia couldn't see what had hit the ground before it was too far away for her to see.

"Hahahahaha! The goth loli landed right by us!" Naruto laughed as he looked behind them. "... So... I could call that a little more than halfway this time."

'He's insane.' Grayfia's hair had come undone.

Her clothes were being ripped up by the speed they were going, yet somehow HIS clothes seemed to be perfectly fine. It was like the clothes that he was wearing were made with so much durability in mind, that even these insane speeds hardly amounted to anything to them.

They increased in speed.

She saw his eyes grow rings around them and turn yellow with bar shaped pupils, and he looked at her for a second. He went full speed and started to go across everywhere, everywhere that he could find.

Then they stopped moving.

"We're... we're here..." Grayfia rolled out of his arms and onto the ground. She noticed a red glow around her body, healing her and protecting her. Her clothes were horribly damaged by the speed that they had reached. "What... what was that?"

"Sorry... I figured using Sage Mode to find the last person I could sense with your energy on them would be faster than direction. Still, going full speed with Sage Mode makes me even faster than the Raikage... not many people can handle going faster than light, so I was using my power to make you more durable and heal the damage." Naruto apologized to her.

Even when Tsunade had gone Light Speed during the war using that technique, she had been required to heal her body, while the Raikage's body had been practically unscratched by it thanks to how he was already capable of moving nearly that fast. He figured this woman would be less durable than Tsunade was, and that she might not have healing abilities, so he healed he started to heal her the second he reached those speeds.

They had reached their destination.

"Grayfia!" A red haired girl quickly approached Grayfia.

'So that is her name.' Naruto thought as he noticed a group of teens, with the red haired girl being the one that had Grayfia's energy signature on her. Naruto put his hands in his pockets as he looked over each of the teens, all of them dressed in casual hiking gear, standing in front of a mansion in the middle of mountainous woods.

"I'm... I'm okay..." Grayfia used magic to restore her clothes and quickly fixed her hair, before she stood up with a neutral look on her face once more. She was visibly shaken though, but she returned to neutrality very well all things considered. "Lady Rias... I have brought a tutor for your peerage."

"Tutor... did my brother hire you to help train my peerage?" Rias approached Naruto with a slightly suspicious look in her eyes.

She was quite beautiful.

"I have no clue who hired me, or what a peerage is. I just know I'm being paid a lot of money to be a combat teacher for your little group. So... you are... who is she?" Naruto asked as he poked Rias in the forehead. She stepped back in shock for a moment, and stared at Grayfia.

"This man has defeated the White Dragon Emperor several times, the SS-Ranked Criminal Kuroka several times, and has defeated Kokabiel as in straight combat. This man is-"

"Uzumaki Naruto! A pleasure to meet you sir!" Rias had actually heard of this man from her brother. Grayfia didn't need to explain who he was for her to know this man by name. This man was famous for the people he had defeated, all of them having sought him out to challenge or breed with him.

There was a sense of excitement in the air.

"You defeated Kuroka?"

"Which one was Kuroka?" Naruto asked the small white haired girl when she came forward and asked him that question with a stunned look. "I don't ask for a lot of names... so... which ones am I training?" Naruto asked Rias as he got a good look at the group.

Rias was now all for the training tutor.

"Yes, since Asia is a healer and a mage type fighter, I think she should train with Akeno. That will leave you with Koneko, Issei, and Yuuto. These three. Issei has the Boosted Gear Sacred Gear-" Rias started, before she stopped when Naruto put his hand on top of her head and grinned.

"I don't need to hear their abilities, what they are good at. My lesson plan will be the same... You don't mind harsh, unforgiving, painful training do you?" Naruto asked Rias, since this was her group that was about to get trained.

"I welcome it! Please, as long as you do not permanent physical harm, please feel welcome to train them however you see fit, for the entire 10 days if you wish." Rias welcomed her peerage being put through the harshest of training. The harsher the training, the stronger her peerage, and the better the results would be in the end.

"7 days... I only need 7 days to get them up to snuff. They can use the last 3 days to rest... after I'm done, they will be asleep for 2 days anyway." Naruto watched as all 3 of the people he was going to be training gulped.

7 days?

"Okay, and might I ask what this training will entail?"

"I'm going to fight them... for 7 days and nights. Don't worry brats, whenever you run out of stamina, I'll give you some of mine, and I'll heal you whenever I get you close to death. So for 7 days, you don't need to worry about food, or your stamina, or anything like that... just do your best to fight me with the best of your ability." Naruto pounded his fist into his palm.

"Buchou, this sounds like a bad idea."

"He's going to kill us!"

Koneko was the only one who remained silent, she just stared at Naruto. She placed her fist into her palm and bowed her head to him, accepting that she was going to get harsh training. Rias placed a gentle hand on top of her head, since she fully understood why Koneko was more serious about the training than the others.

"You can make me stronger than Kuroka in 7 days?" Koneko asked, before she was poked in the forehead.

Naruto poked Issei and Yuuto in the forehead as well.

Their bodies glowed the most light of reds possible as he connected his chakra to their bodies, so that he could heal them whenever he hurt them, and restore their stamina with his chakra. He made sure that they wouldn't be able to use his chakra to enhance themselves though, so that they could only fight him with their own powers. Naruto then wrapped his arms around the trio and lifted them up.

"See you guys later, Rias, follow the sounds of violence in 7 days, and you can see their improvements." Naruto told her as he vanished in the blink of an eye.

Let the hellish training begin.

Chapter End!
Please Leave Me Lots of Nice Long Reviews, But No Flames Please!