Act 1: Demon King Tanjiro

Rise of the Demon King Tanjiro VS Demon Slayer Nezuko

**Originally posted in Fanfiction and Archive**

Published: 04-24-20 - Finished: 07-16-22

Summary: Muzan passed his whole Identity to Tanjiro and is now the New Demon King. He Escaped, people who were present at that day would never forget. How Kamado Nezuko swore back to her brother 'Oniichan, I will definitely, as Your Little Sister...Will Bring you back to normal!' And thus New Pillars and New Twelve Demons are About to Rise upon The Sun Demon King Kamado Tanjiro! Muzan Is always with lonely, isolated Tanjiro.

Kanon58: Hello, this will be my very first KNY fanfic. I had been itching to write a MuzanxTanjiro but too lazy so But this is not yaoi OKAY its like the manga extension lol but im gonna put some bit tease fluffs on ships or slight bromance pff. But my memory sucks on what exactly the lines were in manga so i might change it... i decided this series will maybe 1-7 chaps or 10 who knows but becuz the Manga is nearly end and I want some extension for pure greed. We are now gonna have your awaited Demon King Tanjiro VS Slayer Nezuko! Ufufufu! Also Im not much familliar on other characters so correct me their names lol but for its character personality...mehh its a fanfic its ok if its OOC but I PROMISE NOT TOO MUCH KAY XD

But my English sucks so do Not Except it to be written beautifully or whatever. I'm doing this out of pure fangirling and fantasy.

No Flames you are not a Breath Flame User xD

COME ON BARE WITH ME IM SORRY D:

Im just doing this cuz of Quarantine, But once everything is back to normal I will be busy on my Work again as an Adult. SAD ADULT FAR AWAY FROM ANIMES HUHU

REVIEW To inspire me to update. ROLF

Important note from the REAL author of this fanfic Rise of the Demon King Tanjiro VS Demon Slayer Nezuko: Please report Gaby_Dagohoy who reposted my fanfic here in WEBNOVEL, without my permission...what more he claimed he own this fanfic that I wrote with blood and sweat.

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"Hang in there Nezuko! I swear...your Big Brother is going to Save you no matter what!"

A feeling

"Go to the man named Urokodaki in the mountains...he would..."

A story

"Go Further if you are a Man! Theres no other way to go forward!"

A whip

"I'm glad you made it back..."

An embrace

"Tanjiro...I've been protecting it becuz...you said this thing is more important than your life."

A comrade

"Come on Fight Me! Gamoboko Gonpanchiro!"

A relief

"Kanao, its a Heart that drives people...!"

A dignity

"I leave the rest of my Dream to you.."

A will

"Set your Heart Ablaze...!"

A trial

"The Bond between Me and Nezuko cannot be severe by anyone...!"

A gasp,

If I become a Demon, Probably the Demon Slayer corps would not hesitate to take off my head...

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In Amidst of the Darkness, Random memories surfaces and traces Tanjiro's mind. Slowly he blink and decided to open his human eyes. They were blank and dying.

'...where...am?' he thought to himself. It looks like he was floating. Floating in Darkness.

'I can't feel my left arm...nor I can see in my right eye...?' Tanjiro questioned himself. Quietly and slowly...He recalled something else. 'oh...did I died..?'

Tanjiro had some memories how there is a white haired man monster slashing and bashing around his tentacles with mouths. Then some black haired guy with a indifferent pattern of haori screaming his name in a worried yell.

((Tanjiro! No!))

In the memory where his right eye got whip, Tanjiro wince on the sensation that had already happend. Blood, blood, dead bodies...

There the monster chuckled (("Lets see if you can survive the ounce of my blood. If you do you will become Mine Breath of the Sun User...Kamado Tanjiro~"))

This time Tanjiro responded... "Who...is that person?" the way Tanjiro asks was not asking thy name of the monster, instead questioning who the hell is this Kamado Tanjiro the being speaks off.

'i'm confuse...what was I doing before this place...?' Tanjiro's head started to look around searching for anyone or anywhere can pinpoint his location. There was no one sadly. Only pure darkness like he is being pulled in the abyss. Suddenly a gentle voice who is crying out in desperation calling him brother.

"Oniichan! Dont...loose...! Please! Please Oniichan! Do not kill..Anyone!"

'...what?' Tanjiro's body suddenly was caught by breathing cells. Little did he knew it was Muzan's torn up baby body. It was absorbing him upside down like a glued wall. Another voice was been heard in his working ears. So faint as if the latter saying its last breath.

"Tanjiro...dont make Nezuko Cry...Hurry up and come back... How can you make Nezuko cry?"

'..Nezuko...?'

Tanjiro felt a weird sting on his back. "Ah-!"...'Someone...stabbed me...?' That was Kanao's medicine for him which he doesnt know.

Its not like Tanjiro can see the outside world events or hear them clearly. But his numb body, despite being called numbed-can feel some poking, hugging, breathing, beating. He got irrate on the tugging sensations.

'Im so tired...i really want to go home.' Tanjiro thoughts froze. Home? Does he even have something like that?.

All the inner thoughts disrupt by a advocating voice.

"Kamado Tanjiro...thats right you do not have home anymore." A soft touch on his face and long finger nails pinching him accidentally, Tanjiro now notice a man in pale white skin and silvered hair looking down at him like some flower. Even though the alien person has not told him his name, Tanjiro automatically knew who it was.

"Muzan..." The man chuckled "How fitting it is you had become MINE. Not really mine but had become ONE with me. Ironic." The eyes of the man named Muzan were seductively possessing and it has red orbs like a cat. Tanjiro felt warm. "To think I always avoided your bloodline...If I knew more earlier, I would have taken Yoriichi. But thats a long time ago." Tanjiro kept his mouth apart and breathing. He doesnt want to interrupt the other for some reason. "It happens to be you Tanjiro. You happend to be the rightful heir of my bloodline. My memories, my feelings, all of my everything! I entrust them all to you..." Muzan whispered to him "Fulfill my dreams. As the most powerful Demon King~"

Suddenly mysterious hands popped out of nowhere. Those hands belongs to Tanjiro's family. 'TANJIRO DONT!' His mom said as well the others, his siblings 'Oniichan you have to go back home! Oneechan is waiting for you!'

They were pulling him away from sticky Muzan body.

Muzan knew its the antidote that was injected to Tanjiro not long ago is starting to take effect.

'KAMADO MY BOI YOU HAVE TO FIGHT IT' Rengouku-san's voice.

'TANJIRO-KUN' Said the rest of the dead pillars, their hands grabbed Tanjiro as well away from Muzan's grip. 'GO BACK, GO BACK TO NEZUKO!'

Muzan instead of angry went on panicking "No! Tanjiro! You cant! You are chosen by gods to be my replacement! To carry me with you. Do not leave me be..!" Muzan cried out. The armless side of Tanjiro had decided to look a glance on Muzan. "You..you are going to be lonely if I'm gone?"

He questioned. Muzan is surprised for a second before nodding. "Yes. So come back to me Tanjiro~" the devil smirked.

Tanjiro on the other hand decided to talk to the hands that been calling him by his name yet it did not feel like it was his. "Im sorry...I can sense that I must go with you hands...but I can also Smell that leaving Muzan, he will cry like a baby..."

Becuz he is a Big brother he tend to take care of young ones, especially those who acts like a baby. Tanjiro had now let go of the hands who was trying to ask him not to loose his humanity.

Yes, you guessed it right. Tanjiro does not remember that this Muzan murdered his family, turned his sister into a demon or little did recall he was a Demon Slayer.

Tanjiro whose supposed to be saved by the remaining antidote was not enough to awake him in the abyss.

Tanjiro was catched by Muzan's arms and embraced him tighter with a wicked smile yet also felt so gentle. "Thats a Good Boy. Tanjiro~"

Kamado Tanjiro has been reborn.

"Oniichan...?" Nezuko cupped Tanjiro's cheeks, you see the difference of her two hands. The right hand has bruises, the left hand has ripp off nails. Kamado Nezuko eyes widen when Kanao jumps to stab Tanjiro by the antidote who eventually changed Tanjiro's demonic eyes into calmer ones. Yes he still has demon eyes but atleast they looked similar to Nezuko's 'calmed demon state'

"...Are you concious now?" She ask. Tanjiro's eyes were still glimmering as if they were in a state of shock.

Giyuu who tried to stand again for many times he was been pinned down searched for his sword and gots them to his remaining arm or hand. "...Did it work?" He said out loud, making Zenitsu and Inosuke gulped in anticipation.

Tanjiro's gawking fangs had become smaller. It happend.

Tanjiro looks at his sister "Ne...zuko." upon hearing that Nezuko smiled with tears in relief. "Oniichan!"

But

She suddenly got pushed off.

Everyone is shock. Tanjiro stood with a sad smile "Im sorry."

Then he vanished.

Eyes still widen like the sun had risen above. Nezuko was fumble. "ONICHAAAAAN!?"

Kamado Tanjiro disappeared. He had escape!

Giyuu fell to his knees in defeat "Noway..." he slammed his remaining fist to the ground "...I knew it, the small ounce of antidote is not enough...!" Giyuu cried out but not as much emotional that he did before when he thought Tanjiro died in sitting position.

Nezuko started to cry as well with her bloodied body. "No! Come back...Oniichan...dont leave me be...!" She sniffs.

Zenitsu who was able to regain control of his body casually walks near Nezuko and pats her shoulder. "Im sorry about Tanjiro...Nezuko-chan, but I will be by your side..." tears fell on Zenitsu's eyes. Nezuko slowly looked at the blond haired and realize the situation. 'Im not the only one who is grieving about Oniichan'

Nezuko saw Inosuke whose slamming his own body at the debris "No! NO! TANJIRO COME BACK HERE! YOU...ARE HARD HEADED! COME BACK! COME BACK AND FIGHT ME!" Inosuke's mask fell off and he is crying the most out of the four.

Nezuko then realizes Kanao whose bleeding out on the ground. "K-Kanao-chan..!" Nezuko reaches her hands and hug them for comfort.

Kanao was...was alive. But she is staring blanky. "Tanjiro-kun..." Kanao said as she heaves a bit "Nezuko-chan...did Tanjiro-kun not revert back?" She asks as if she did not see it. Nezuko gasp and tighten her comfort to Kanao's hand. "Im sorry Kanao-chan...Oniichan, Tanjiro is still a Demon, and he escape..." she hoarse. Nezuko is guitly because Kanao sacrificed her eyes for this one shot antidote but it was in vain..!

However Kanao's left eyes glimmered. It slowly made its way to stare at Nezuko. "Dont cry Nezuko-chan," she smiles "My right eye was not completely blind for some reason...but it is blurry and hard to see now." Nezuko doesnt know how to react if thats a small miracle or just simply suffering from now a poor eyesight. "Nezuko-chan, Im the one who should apologize." Kanao's eyes starts to produce tears and they fell.

"Sorry for not being able to bring your Brother back. I really am...sorry!" Kanao hicks. She isnt the emotionless Kanao that we knew. She has a heart now, and a smile and thoughts raised like the Kochou sisters. "Im sorry Master, neesan...!" Kanao cursed herself.

The kakushi's whose on the scene started working their bodies to aid all their injuries once more. "Quick! The battle is never over! We must heal them properly! They are our remaining hope..!"

All of the present Kakushi felt the determination and nodded to eachother. They begin from zero. First aid.

Nezuko whose tears actually subside had ignored Zenitsu whose hugging her back. Nezuko had let go of Kanao's hand as both of them is now been told to get treatment. Zenitsu was pulled away by a male Kakushi.

Gently a female Kakushi touch Nezuko's back "Let me see how deep is your wounds-" the Kakushi paused. The wounds were not that deep despite the large soak of blood trails. 'Thats...weird.'

Nezuko looked at her, "Is my wounds that bad..?" Nezuko is worried for a second. She did not want to die like this. The kakushi smiled despite the mask on her mouth and shakes head. "Nno...infact im surprise to see it was not that of nasty as We could imagine."

"Okay...please take care of me." Nezuko softly smiled but you can clearly see as well she is pretending to be not depressed.

Giyuu whose treatment is done immediately approached Nezuko. "Nezuko.." he called.

Nezuko looks up to the man she recall in her memories that spared her life from the bloodied snowy day. "Giyuu-san..." Giyuu bowed his head. "Im responsible. Now that your brother, no...now that Tanjiro had escape we cannot guarantee him eating a human." Giyuu bit his lips. "Your case was different, you were stop to eat any human flesh becuz of the bamboo gag I made."

Nezuko turned serious. She knows exactly what Giyuu is fearing.

Nobody can stop Tanjiro to eat someone. Meaning he would sunk further to demonification until he cant be revert back to a human anymore even if the antidote gets replicated.

"The antidote did work." Nezuko claims, making Giyuu snaps his head in a puzzled face. "Onichan, no Tanjiro my brother he called my named with a sad smile. You guys saw it right? That means the medicine did work a bit...means Onichan can fight back the hunger just like I was able to! Im sure he is just confuse just like I was back then...thats why maybe he run away..." Nezuko said stubbornly "Kamado Tanjiro will never eat anyone!"

Giyuu did notice that but he didnt want to have high hopes. "I will get him!" Nezuko stood as she knew that the medic is done with her wounded back but it needed to have some bandages. Nezuko glared, not for Giyuu but glared like a fiery sun. Determination was there and it flared more than Tanjiro's eyes. "I Kamado Nezuko will bring down the Demon King and Return him back as Tanjiro! My beloved Brother!"

Everyone who is there heard Nezuko's statement. Gawked.

Zenitsu realizes this means ..."Nezuko-chan do not tell me you are planning to..."

Nezuko glance at Zenitsu's whose having treatment. Nezuko smiled, "Yes Zenitsu-kun. I will become a Demon Slayer. I will save my brother just like how he saved me and everyone else...so please help me okay?"

That sunny smile made Zenitsu cry like a whimp he thinks he is. "N-Nezuko-chan...!"

"Stop wiggling around idiot!" The Kakushi warned as he was trying to put another layer of bandages from Zenitsu's injury. Zenitsu nods and oaths to her. "You are my wife! So I will protect you..! Wuu!"

Nezuko startled by that statement "W-wife?!" With a bit blush, Inosuke joined the converstion by approaching as well. "Nezuko...chan" Inosuke said with his face revealed with pink tears. "For Tanjiro, our brother we will save him together!" Inosuke jump to cuddle on Nezuko "I swear to!"

A vein pop appeared in a jealous Zenitsu "Hey! Dont hug my Nezuko-chan!" Zenitsu left the male Kakushi whose now angry at him and jumps to hug with Nezuko "We do it threesome!"

Inosuke whose crying suddenly snaps to Zenitsu "What are you even saying! Go back to sleep like you used to!"

The two started to argue.

It made the atmosphere bit lighter.

Nezuko fell a smile of support from them. Giyuu talks to her.

"Look, Im not stopping you but the training to become a Demon Slayer is not that simple." Giyuu did saw Nezuko fighting style as a demon, and defintely girls are strong too like Kanae,Shinobu and Kanao especially Mitsuri. He is a bit worried to Nezuko who is now human, wonders how this girl will fight.

"You have to train like your brother did. I will train you or set you off back to Urokodaki."

He spat.

Nezuko agreed on a nod. "Im willing!"

2 years Later...

The new appointed littled version of Ubuyashiki is here...Oyakata Sama.

The new head or the boy who look exactly like his father positioned to face the people who went to his meeting proposal.

"Thank you so much for coming. Its been a pleasure that after what happend with Kamado Tanjiro, the will in your eyes were not faded to fight."

He eyed all of them

The right had the following adults...and one kid.

Uzui Tengen, Shinjuro Rengoku, Senjurou Rengoku, Sankonji Urokodaki, Tomioka Giyuu.

The Left side had the noticiable teenagers.

Agatsuma Zenitsu, Hashibira Inosuke, Tsuyuri Kanao, Aoi Kanzaki.

On the front seated were Yushiro and Kamado Nezuko.

In between Oyakata sama were his sisters sitting as well with the dollish smile they were trained to.

"2years had passes...There was not a single demon incident." He was suspicious of that. "But I thank you for still keeping your bodies in shape despite the tranquility of 2years." His eyes turned serious and everyone could sense the next word will be.

"The Demon King Tanjiro we must find him wherever he is and bring him back to humanity, if that is he has not devoured any human being." Since there was no reported people got eaten by any demon they can safetly assume that Tanjiro might be asleep like how Nezuko went to sleep on her demonification days.

"We must stop him before he really becomes the New Demon King worst than ever Muzan has been." He closed his eyes for a second before opening them again. "We are in a desperate situation for Pillars. So I will assigned you now."

Water Pillar Tomioka Giyuu

Beast Pillar Hashibira Inosuke

Flower Pillar Tsuyuri Kanao

Ice Pillar Aoi Kanzaki

Smoke Pillar Senjurou Rengoku

Lightning Pillar Agatsuma Zenitsu

Fire Pillar Kamado Nezuko

"I order you to set off in search of Kamado Tanjiro and protect the people from his mercy!"

Everyone replied with loud and willful voice. "Yes! As you command thee, Oyakata-sama!"

Nezuko looked at her Nichirin sword, she clutch her hands to her Demon Slayer uniform and she is wearing A pink Haori that looks like her former kimono.

She thought

'Oniichan, I will definitely, as Your Little Sister...Will Bring you back to normal...!'

Somewhere in the Butterfly estate...Shinazugawa Sanemi opened his eyes. There was a flutter of curtains around him. Sanemi did not know that he was in comma for freaking 2years. He the only person not aware what happend to Tanjiro.

"Why the fuck am not dead...?" Is the very first word came to his mouth. He close his eyes again in irritation of the light..."Damn this."

He rolled on his bed and kept himself on bed like a goodboy...

Marechi...huh

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Somewhere a abandoned mansion that is already in ruins. Its one of Muzan's human mansion that Tanjiro took cover.

Tanjiro had his hair longer, hanafudda earrings in his ears, tongue that licked his fangs. Eyes that were absolutely alikes to Muzan. Marks of flame in his body like what he looked like when he was turned into demon.

But he is wearing a black kimono like Muzan's yet a green checked scarf that looks like his torn Haori.

Tanjiro faced the moon with sleepily eyes. "Hey...Arent you guys gonna talk to me?" He smiled at the darkness.

There a figures of human beings.

Revealed a demon version of the Pillars. They finally spoke to him as he wished for...

"ARA~Ara~" Kouchou Shinobu

"S-Sorry master!" Kanroji Mitsuri

"We do not know what to say..."Obanai Iguro

"If its your wish to talk to a low person like me am most pleasured~!"Muichiro Tokito

"Ahh, ahh our King is fully awake now" Himejima Gyomei

Last but not the least Kyoujiro Rengouku.

"Tanjiro-sama...!" He kneeled. "We are here to serve your wishes...! State it!"

Kamado Tanjiro is sitting on a luxurious king chair it seems. His smiling teeth widen. "I'm hungry."

And thus the Battle between Tanjiro Vs Nezuko begins..!

To be Continued

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Kanon58: plz review and tell me ur thoughts. Btw Makomo,Sabito Genya will be the lower moons in future..ahhh spoiler! Nahh not really. Hope you enjoy the first chapie!

Next: Nezuko trained with Urokodaki and Giyuu, We will see Tanjiro's struggle within that 2years...