Calm, before the Storm

Muzan's body slowly disintegrated, as the sunlight burned his body into ashes. As his body faded away, the surrounding area turned deathly quiet, watching the source of all their woes, their archnemesis, the King of Demons dying before their eyes.

The last pieces of Muzan crumbled away, disappearing into the bright sky.

"I-Is it… over?" Someone muttered.

A Demon Slayer spoke up in disbelief. "H-He's dead… Muzan is dead!!"

From that declaration, everybody broke out into hysterical cheers. People cried in relief, joy and grief.

"Uwwaaaahhh!!"

"We beat him!! We beat Muzan!!"

"Muzan is dead!!"

Everybody began to celebrate with one another, crying for the people who gave up their life for this fight.

"It's not over!! Stand up!! Help the Injured!" A Kakushi shouted out to the others. "Hurry, go around and give aid!"

The people who were grieving and rejoicing immediately switched gears, running to the injured and lent them aid.

Laying on the ground, Hiroto slowly sat up as multiple people appeared around him.

"S-Sir! Please, don't move!" A nervous Kakushi said as she tried to stop Hiroto from moving.

"Tanjiro," Hiroto muttered as he stood up. Standing up in full view, people noticed that his wounds had recovered completely, leaving behind no scars.

"S-Sir… Y-Your wounds…" The woman muttered in disbelief, seeing his heavily bloodied uniform, but his body in pristine condition.

"Where's Tanjiro," Hiroto muttered again, as the Kakushi were still lost in their thoughts. Hiroto felt something in his calling out to him, as he turned to a specific direction that felt familiar.

Walking away, the people around him didn't know how to react, as they looked at each other.

Hiroto kept walking forward, passing by countless people who were tending to the injured. He felt his skin burning, but then immediately subsiding a moment later.

"Hiroto…" A familiar voice reached him from the side, as Uzui was being tended by multiple Kakushi from his wounds. Uzui saw the state Hiroto was in and tried to speak up but was overwhelmed with pain and fatigue.

Hiroto walked further until he saw the familiar figure of his younger brother, Tanjiro, laying on his back as multiple Kakushi tended to him.

Hiroto just then realized he was still gripping onto his sword. Hiroto looked at his sword for a moment, before dropping it to the ground as he walked forward to Tanjiro.

Hearing someone come close to him, Tanjiro, who had the severed part of his left arm bandaged up, turned his head and smiled tiredly as he saw his brother, "Big brother… We did it." Tanjiro smiled.

Hiroto knelt down next to Tanjiro and smiled back, saying, "Yeah… we did it. We defeated Muzan."

Tanjiro then covered his eyes with his remaining arm, crying softly as he said, "Mother… Takeo… Hanako… Shigeru… Rokuta… we did it. We avenged you… Please, rest in peace now…"

Hiroto smiled tiredly, and said, "They would be proud of us. Of you. No one else will have to go through what we did, not anymore."

Tanjiro removed his arm and got a proper look at his brother's appearance for the first time, causing him to speak up. "Brother… You…"

Hiroto looked at his body and nodded slowly, "I know…"

Tanjiro stayed silent for a moment, then asking, "Do you… feel anything?"

Hiroto shook his head and said, "I don't know. I only felt like I was burning a moment before, but it faded away soon after Muzan dissipated."

"Hiroto...Tanjiro…" Giyu's voice reached them from the side, as he knelt down next to Tanjiro, opposite from Hiroto. "I'm glad you're both okay… You two did it… You defeated Muzan."

Hiroto shook his head and said, "No. We all did it. Without anyone else, we wouldn't have been able to do anything, and Muzan would still be alive."

Giyu looked as though he wanted to say something but stopped, as he just smiled and said, "I'm just so happy you're both okay."

Hiroto then suddenly gripped his head, catching the two off guard.

"What's wrong?" Tanjiro asked, "Are you still wounded?"

"I-It's fine," Hiroto said, shaking his head. Suddenly, Hiroto grabbed his head again in pain as he quickly stood up, crying out in pain, "Grahhhh!!"

"Wh-What's going on?" A Kakushi from the side asked as he stepped back from surprise.

"Arggghhhh!!!" Hiroto yelled out, as he fell onto his knees, as he continued to hold onto his head.

Giyu's eyes widened, as he saw Hiroto's eye color change to red, and his pupils narrowed, similar to a Demon's. Drool began to fall out of his mouth, as the nails on his hands grew razor sharp.

Hiroto's eyes looked around the area quickly, eyeing the blood on people's clothing, ground, and body.

Giyu immediately saw this and pulled Tanjiro away, shouting out, "Get away, NOW!!"

"Wait-" Tanjiro tried to protest, but was flung away by Giyu into the arms of the Kakushi behind him.

"What? Why-" A Kakushi tried to speak out, but was interrupted as Hiroto swung his hand forward at him.

However, just as the hand was about to hit him, it stopped. Trembling, Hiroto's face had a grin and painful look at the same time, as he forced himself to stop his arm.

"Anyone who can move!! Grab your weapons and get over here nooow!!" Giyu shouted out at the top of his lungs, sweat and a sense of dread filling his body.

Everybody turned their attention to the shout, as they began to stumble and run towards Giyu's cry.

"Hiroto has been turned into a Demon! The sun won't work on him, kill Hiroto before he kills someone!!" Giyu shouted out, as he had a pained expression from having to utter those words out.

Hiroto was still trying to control his arm, when his left arm suddenly moved and jabbed it's finger into his brain, causing him to pause in his movements.

Giyu took this chance to charge forward and swing his sword towards Hiroto's neck.

*crack*

Suddenly, Hiroto snapped out of his daze, as his body bent backward, fracturing the spine in the process, causing the sword to completely miss.

*BOOM*

Hiroto elbowed into Giyu's chest, causing him to spew out blood as he was launched away.

Hiroto crouched on the ground, as his body swung upright, snapping the spin back into place. Looking at his hands, Hiroto grinned wickedly to himself.

On the side, Tanjiro was being held by some Kakushi as he slowly spoke out, "No… This can't be… Big brother… please, not you too…" Tears fell from his face, as Tanjiro saw in the corner of his eye, a familiar crimson and purple looking sword.

The mark on Hiroto's arm and face spread, becoming more concentrated than ever before. From the side, Inosuke and Zenitsu stood in disbelief as they stared at Hiroto.

"This can't be real… Hiroto…" Zenitsu slowly said, tears falling from his eyes. "Nobody can fight anymore. We're all worn down. This is just too much, and what about Nezuko? Tanjiro?"

Hiroto then looked towards where Giyu was, and then jumped forward with extreme speed, swinging his hand towards Giyu's head.

*swish*

Out of nowhere, Rengoku and Inosuke appeared and sliced Hiroto's handoff, as Inosuke pushed Hiroto away.

Rengoku had tears streaming down his face, as he tried to keep calm and shouted, "Of all people, why did it have to be you, Hiroto!"

Hiroto growled as he jumped back, crouching on the ground with a fresh new hand. "Grrr!" Hiroto gave off a deep growl, as he eyed Rengoku and Giyu with hatred filled eyes.

"What the hell are you doing?!" Inosuke shouted from the side as he ripped his mask off with tears streaming down his face. "That's the mix-matched haori guy! That's our friend!!"

*BOOM*

Hiroto kicked off the ground, destroying it in the process as he jumped forward and went after Rengoku and Inosuke.

*swish*

Rengoku swung his sword at Hiroto, who deflected off to the side with his claws. Inosuke then swung his swords down at Hiroto, who dodged to the side and thrust his hand towards Inosuke's heart.

*shik*

"Grahhhh!!!" Hiroto cried out, as he felt a sword pierce him from above, with someone pinning him down.

"Brother!! Please!! Stop this!" Tanjiro cried out, as he used his right arm to pin Hiroto to the ground with Hiroto's own sword.

Inosuke on the side prepared to swing his sword to decapitate Hiroto, but faltered, as he remembered back to the time the three of them were at the butterfly estate, eating and laughing together.

"I...I can't, Tanjiro. I can't slice him." Inosuke muttered, with his arms trembling. Tanjiro shut his eyes to try and stop himself from crying.

"Grahhhh!!!" Hiroto cried out, as multiple spikes surged out from his back, knocking.

"Tanjiro!" Rengoku shouted, jumping in the way and knocking Tanjiro to the side, as one of the spikes pierced into Rengoku's leg.

"No!!" Inosuke shouted as he cut off the spike that was embedded into Rengoku's leg.

Hiroto then turned and jumped towards Inosuke and Rengoku, but was pushed to the side, as Tanjiro tackled Hiroto to the ground and held him there.

"Brother!! Please!" Tanjiro yelled out, as he held Hiroto to the ground. "Don't hurt them!! Please, come back to us!"

Hiroto gripped onto Tanjiro's hair and was about to rip Tanjiro's head off when he suddenly stopped, with his arm trembling. Hiroto's eyes widened as he stared at Tanjiro's face.

*THUD*

Muichiro appeared and knocked Hiroto away from Tanjiro, as he kneeled on the ground in pain and shouted out, "It's useless to try and reason with him! He's a Demon now!" "Wait! He stopped for a moment! He could still return!" Tanjiro quickly shouted out, but then saw Muichiro's eyes that were also tearing up.

Muichiro said, with his hands trembling. "It also pains me, but we have to do this, Tanjiro. Your brother… is gone."