Disclaimer: First Chapter
Story Start!

"Ah... another set of boring challengers."

Naruto Uzumaki had an extremely fuzzy memory of the things that had happened to him up to this point, though he knew the facts that he USED to be a human, and was now a demon. He had a craving for human flesh, though he had yet to eat any and his stomach was growling. He couldn't go out in the day, he just felt the instinct in him that day walking was about as bad of an idea as they came.

4 demon slayers lay on the ground in front of him.

Defeated, broken, but not dead.

"Go on... shoo... your blood makes my mouth water." Naruto waved them off. The longer they stayed, the hungier he was going to get. He was going to have to kill some strong predator animal to sate his hunger for the moment after they left. He flipped his sword back around and sheathed it, having only used the blunt end to attack them the entire time he toyed with the novice swordsmen and women.

-Days Later-

"Another group... injured... but nothing life threatening."

More than 40 of their lower ranked demon slayers were all in bed, bandaged up and unable to move well, but alive and in stable condition. Broken bones being the most serious of their injuries, but no bite marks, and all of them having the exact same story to tell them about their mission. How no matter how many of them approached him, none of them could so much as lay a single blade on him.

The Demon of Mt. Kurama.

Not even demon slayers of the Kinoto or Kinoe ranks combined were able to get him to take them seriously.

"... These wounds were deliberate... made to wound, inflict great pain... but not kill, or prevent them from fleeing... a demon did this?"

Shinobu, a Hashira of the highest rank, looked at the medical charts of every single member who had been injured. It was her medicine that was being used to heal them, and her group that were allowing them to recover safely. A demon that didn't kill demon slayers and allowed them to run away freely was strange, but it wasn't completely unheard of for a demon to play the long game. A demon that defeated over 80 demon slayers from, ranging from every rank other than Hashira itself was unheard of though.

"Could you tell how many humans he had eaten?"

"... From what I sensed, he hadn't eaten anyone yet."

"... He must be starving... a starving demon shouldn't have the willpower to avoid eating... and for this much power to be held by a new demon." Shinobu dropped her smile for a moment. If a Kinoe rank said that a demon hadn't eaten anyone, she was very likely to believe them. That was the highest rank of demon slayer, other than her own rank of Hashira, the elite of the elite. "... he must have been an absurd human... did you get his name." Shinobu asked the defeated corps member.

"Uzumaki Naruto."

"... That name sounds familiar." Shinobu had heard that name from somewhere before, but she couldn't recall where she had heard it before. She felt like she had at least read about that name from somewhere, even if she had never heard it in conversation. "... I guess this is a job for a Hashira... I wonder what meeting him will be like." Shinobu would wait until there was another Hashira that could come with her.

She wondered what Giyu was doing?

-Weeks Later-

"Yuck... what a man wouldn't do for a bowl of ramen."

Naruto lamented his current situation, and sighed in boredom as he ate a deer. He cooked it for flavor, but that was about it. It sated his hunger enough to keep him sane, but didn't get rid of the craving he had in his core.

A demon slayer was coming.

"... Is it one, or two... seems strong... maybe it won't be boring." Naruto stopped eating and moved to sit outside, and he stabbed his sword into the ground. He just leaned forward, placed his hands on the handle, and just grinned pleasantly.

He waited.

They were walking, and taking forever with it. He started to tap his foot against the ground, his smile twitching with just how long his enemy was taking to approach him.

She arrived.

"... Well this is disappointing... and after you kept me waiting." Naruto saw a woman, more than a foot shorter than he was. She didn't even reach the 5 feet point in height, and while she had some serious development in her chest and hips... when it came to her arms, he could see that she lacked the strength needed to cut his head off. He could tell that she lacked the sheer physical strength needed to give him a challenge.

"Excuse me?"

"Don't worry about it... I'll tell you the rules."

"Are you Uzumaki Naruto, Demon of Mt. Kurama?" Shinobu asked as she clicked her sword out of it's sheath slightly, she was ready the moment it looked like he was going to try anything. If his strength was as strong as it had been shown, making the first move would be a mistake. She didn't know what his skills were, and most slayers had only vague memories of what he could do with a sword.

Naruto nodded his head.

"Rule 1: Come at me with every intention to kill me, or you won't even scratch me. Rule 2: Never turn a blind eye to me, or you will regret it... Rule 3: Always keep your eyes on my sword and feet, those are the best ways to tell what my next move will be."

Shinobu frowned as her enemy stated rules, but the rules were just methods to make the fight against him even easier for her. He was giving her tips on how to kill him best, which meant he seemed to be underestimating her. She didn't say anything, or even allow her offense to show on her face. He just lifted up another finger, and showed there were even more rules for her to follow.

"Rule 4: Have fun."

"... Have fun?"

"Yeah... helping people grow stronger is fun. So once you lose, be sure to come back and try again as many times as you want... get as strong as you can, and only when you have reached your peak, will I kill you." Naruto stood up and placed the palm of his hand on his sword.

"Uzumaki Naruto... wanted ronin, a man who attained the cursed name of Thousand in One Man... a man who slaughtered an army of 1,000 samurai in a single night. That was who you were as a human." Shinobu reached into her pocket and showed Naruto a wanted poster of him.

...

"That is horribly drawn... that barely look like me at all... 1,000 men... sounds about right. Seems like something I could do-" Naruto kicked his sword up and blocked a stab from Shinobu. He placed his finger against the side of his sword and pushed her back, and she crossed the distance to escape any counter attack. She had used the poster as a distraction against him.

Shinobu sheathed her sword again and took up a different position.

"You murdered humans."

"Meh... was it self-defense, was it war, what were the conditions that caused that." Naruto watched as she zipped forward, in a zig zagging pattern faster than a normal eye could see. She cracked the stone underneath her as she moved, and she unsheathed her sword.

"Dance of Centipede: Hundred Legged Zigzap."

'The speed is absolutely amazing, she seems inhuman in that aspect... but her arms lack the strength to do a finishing blow against a demon.' Naruto caught the tip of her sword in his hand, as his other hand went towards his own.

Shinobu backed away and ripped her sword out of his hand.

He cut off his own hand in an instant.

"Poison! That is how you do it! Now THAT is amazing, no wonder you kept sheathing your sword... THAT is something-" Naruto saw the hand he cut off turn purple and get destroyed, and he instantly grew back another hand. The sword she used had no normal blade, but instead looked like a sharpened stinger made for injecting poison. "... even without the strength to cut off a head, you worked your speed and agility together, and found a way... now THAT is the embodiment of the human spirit!" Naruto laughed and leaned forward, holding his gut.

Shinobu was smiling.

'... He reacted to me... a demon has never reacted that way to my speed or poison. The second the poison was injected into him, he realized what happened and cut his infected hand off.' Shinobu watched him carefully, putting both her hands on her sword. He wasn't moving towards her, instead he looked at his own sword.

"Then there was a sound... you breathed differently right before you went on the offense. The others did something similar... Breathing styles... heh... I might try and make one for myself."

A vein appeared on Shinobu's forehead, but she pushed a smile onto her lips. She held herself back from saying anything.

"Why haven't you eaten or killed anyone... if you are this strong."

"Because, eating humans is gross... duh... yeah, you smell and look delicious... but the fact is, I was once human... if humans can become demons, that means demons might be able to become human... meaning eating humans is still cannibalism... and that is gross." Naruto explained his logic to her.

"No demon has ever become a human though."

"So... if there was a first human to become a demon, that means eventually there will be a demon who becomes human... and I'm just not interested in picking on the weak. Killing people weaker than me when I have the chance not to kill them is just bullying." Naruto pointed his sword at her. "Rule 3-"

Shinobu was caught off guard when the light of the moon glinted in her eyes, and she started to move back, but stopped.

She saw a flash of his sword, and he was on her. He stepped forward, his foot between her legs and stopping her footwork from any complex techniques. His arm extended over her body, and his sword was pressed against her back, with his forearm pressing against her shoulder.

'At this distance, I can't unsheath my sword and attack... and with his sword on my back, I can't retreat... he is too close to attack, and his leg makes it impossible for me to move to either side, not without tripping...' Shinobu couldn't lean back or do any movements or risk his sword cutting her back open.

He elbowed her in the face.

Her nose crunched and he took his sword back so she didn't cut herself when she was knocked backwards. She regained her balance and created instead of getting as far back as possible.

"Your techniques use your small, bug-like size, combined with your inhuman speed and agility in order to make your attacks hard to predict and block, and dodging is hard with your speed... but you need excellent eye sight and reaction time to pull it off... thus if your mobility is restricted and reaction time hampered... got it." Naruto analyzed, broke down, and countered her fighting style. "Remember rules 1 through 4... I never got your name."

"..."

"Come on... I'm not going to fight you anymore if you don't tell me your name." Naruto complained when she just gave him a glare. The smile on her face looked like at any moment it could break, and more veins started to appear around her face.

She was pissed.

'Calm down... full speed, I have to go for the neck... nothing else will work.' Shinobu reached up and snapped her nose back into place, blowing the blood out of it.

Naruto dropped his smile.

"Full speed... I'm going to inject poison into his neck, because he can't cut that off, nothing else will work... well I'll give you that... you are following Rule 1." Naruto told her. He sighed in disappointment. "... come at me when you're ready." Naruto flipped his sword.

He watched her take a deep breath, and the veins around her entire body became more pronounced. She rushed him with her absolute full speed, enough speed that he couldn't even see her attack. She was faster than his eyes could see.

*SNAP*

Shinobu's blade snapped when Naruto struck her blade with his sword, not looking at her face, her sword, or anything. He kept his eyes unfocused, not relying on them in the slightest in order to react to her attack.

"As long as you know the enemies fighting style, and their goal... even if they outspeed you... you can guess where they will attack. People can only move at full speed in a straight line... you weren't going for my back... you were going for my neck... with your sword and size, you were going to attack from below... that left only a small window for you to attack." Naruto showed that he had her arm in his other hand. "... You're not suited for this..."

"Huh?"

"You're going to get killed and eaten by a demon... a skilled demon, or a demon your poisons won't kill right away... you don't have a chance to survive against them. This is the limit of your strength..." Naruto let go of her arm.

'I still have-'

"The fight is over now... breaking your bones won't motivate you to grow stronger. Anything else I do to you will only be needless and cruel... the fight is over." Naruto sat down, and stabbed his sword into the ground. He had no desire to continue fighting her if this was the limit of her strength.

Shinobu was frozen in place.

"What?"

"Rule 4... have fun, and it would be breaking Rule 4 if we continued fighting. I've broken your sword, your speed is-" Naruto grabbed her foot when she rushed forward and kicked him. She took the broken part of her sword and dug it into his forearm. He cut his arm off, grabbed her foot twisted it, and pushed her away. "... go, leave... your hands weren't meant for killing... I can't in good conscious-"

"Demons don't have that!"

"...I'm done fighting you. Your sword is broken, and so is your ankle... your speed has been reduced, you no longer have your full sword's range of power..."

She moved.

Naruto smacked his fist into the side of her head, and she went down. She collapsed down, unconscious, like a log with her eyes rolled into the back of her head. Naruto looked at her, and she woke herself up.

He stepped on her torso.

*Crack*

"Stay down... the fight is over, and it is time for dinner." Naruto grabbed the unconscious woman and dragged her by the shirt towards the house. Naruto heard the cawing of a crow, and saw one flying away.

-Elsewhere-

"I see..."

It quickly spread.

The news that Shinobu had fallen in battle, that she was dragged into a house to be eaten by a demon quickly spread among the demon slayers.

Giyu felt regret.

'... I should have gone with her... this must have been one of the Upper Moons.' Giyu shouldn't have rejected her proposal of going with her to slay the demon. He had believed her to be strong enough to handle it on her own, but he had just assumed it was a strong demon, not a demon with strength on par with an Upper Moon. '... Demon of Kurama... I will behead you.' Giyu promised himself.

He would have revenge for his fallen comrade.

Chapter End!
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