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Muichiro’s insides felt like they were burning. Muzan’s voice was getting louder in his head. He had to kill himself before he became a demon. But his sword was still pinning him to the column, and he didn’t have the strength to pull it out. He tried to find Genya, but his vision was hazy, and he could barely hear anything over the gushing blood in his ears. He tried to call out for someone to kill him, but only a guttural half-scream came out. His head was throbbing with pain. Muzan’s voice was now louder than ever, and…
He must have blacked out. He didn’t remember what led to him blacking out. In fact, he doesn’t remember anything about his past except for three things. First was his breathing technique. Second was the Demon Slayer Corps, though he has no memory of his life there. The third was the other demon in the room. It was his ancestor, and right now, he was in the midst of fighting a wind breather. He smelt delicious, and he only just realised how hungry he was and the sword impaling his shoulder.
He took out the sword. His wound healed almost instantly. Someone screamed, and he felt the vibration of slashes. Kokushibo stepped in front of him and deflected the wind breather’s sword.
“Do not hurt Muichiro-kun.”
Was that his name?
“TOKITO, YOU MUST RESIST!” the wind breather yelled. He looked furious, and yet Muichiro saw desperation behind his eyes.
“Muichiro-kun, these demon slayers are trying to kill Muzan. It’s our job to stop them.” Kokushibo spoke calmly as if this situation was no bother to him.
He might not remember much, but he knows he was created to protect Muzan against these demon slayers, which means he’ll have to deal with this wind breather. He smelt another human in the room, but he seemed of no significance at the moment. Though, it might be a good idea to eat him now.
Muichiro zeroed in on the harmed slayer, if you could even call him that. He was cut in half yet was still very much alive. How odd. But blood was pouring out of him, and it smelt absolutely delectable. Muichiro didn’t even need breathing techniques to move fast, and before anyone could react, he was on top of the fallen slayer.
“NO, GENYA!”
The wind breather was on him in seconds, but Muichiro deflected his blade with ease.
“WIND BREATHING SECOND FORM: CLAWS-PURIFYING WIND!”
“Mist Breathing Third Form: Scattering Mist-Slash.”
Their blades clashed in a swirl of mist and wind. Muichiro was impressed by the wind breather’s strength as he was able to push him away from Genya.
“TOKITO, YOU MUST RESIST. COME BACK TO YOUR SENSES.” The wind breather was staring at him in desperation. A little softer, he said, “I know it’s possible.”
What is he talking about? He is a fool if he thinks he can sway Muichiro to stop fighting him over a few pleas and tears.
Just as their blades came apart, a large crash came. Muichiro felt someone grab him, shielding him from whatever that crash was.
“Are you okay?” Kokushibo asked, looking down at Muichiro with concern in his six eyes.
“Yes,” Muichiro answered, looking past his shoulder to stare at the newcomer. He gulped. This man was a mountain. He’s reached peak physical form. His arms and legs were as thick as tree trunks. His hands alone could probably crush Muichiro’s skull. This man was a threat, and he shook every nerve in Muichiro’s demon body.
Kokushibo turned to look at the man. “A worthy opponent,” he commented, taking in the slayer’s physique. He turned back to look at Muichiro. “Don’t worry about him, Muichiro-kun. I’ll deal with him.”
The man’s grip on his weapon tightened. It was an odd weapon. A giant axe and flail attached by a chain. Only a giant could wield such a weapon.
“What have you done to Tokito?!” the man demanded. Despite the man being blind, he stared right at them.
“Were you the one taking care of him?” Kokushibo asked calmly. “I give you my gratitude, but–” he raised his sword– “I can’t have you attacking him. As my descendant, it is my duty to protect him from threats he cannot face himself. I will not let you take his life.”
He slashed his sword; crescent moons forced the two slayers to fall back.
The blind slayer gritted his teeth. “Shinazugawa, try to get Tokito back to his senses. If you can’t, kill him. Stone Breathing Fourth Form: Volcanic Rock, Rapid Conquest.”
“Moon Breathing Second Form: Pearl Flower Moongazing.”
Kokushibo and the stone breather initiated their fight. Meanwhile, the wind breather appeared right before Muichiro.
“Wind Breathing Second Form.”
“Mist Breathing Sixth Form.”
“Wind Breathing Ninth Form.”
“Mist Breathing First Form.”
Their blades kept clashing and clashing. It seemed neither of them could get the upper hand. They were too evenly matched, and Muichiro was starving. That fallen slayer would be the perfect meal, yet this wind breather was in his way. Well then, if he can’t eat the fallen slayer, he’ll settle for the wind breather.
“Mist Breathing Seventh Form: Obscuring Clouds.”
The wind breather tched, scanning his surroundings to try to spot Muichiro. He slashed frenziedly at nothing, and when Muichiro got close enough to be spotted, a large opening was waiting for him. The wind breather took in a sharp breath as he spotted Muichiro.
“Oh fuck,” the wind breather cursed, but before Muichiro could slash him, he fired a gun at him. His blade only cut through his haori as Muichiro stumbled back.
His skin would regenerate, though not as quickly as he would like. He needed to eat a human now.
Muichiro took his stance, positioning his blade to perform the fifth form when the wind breather spoke. “Tokito, come on! I know you’re still in there! You haven’t eaten a human yet! You might not go to hell! You don’t deserve hell, you hear me, Tokito!”
“Way too clearly. You don’t need to shout, you know. I’m right in front of you.”
The wind breather huffed in amusement. “Still the same old Tokito,” he mumbled to himself.
Muichiro ignored that comment. This wind breather knew nothing about him. Muichiro was sure he'd remember a face like his. His strength alone was too valuable a piece of information not to remember.
“Your words hit just as effectively as your blade. So are you done? Because I’m hungry and I need to finish you.”
The wind breather gritted his teeth. He had a…pained expression on his face. “I guess I’ll have to kill you. Wind Breathing Seventh Form: Gale, Sudden Gusts.”
“Mist Breathing Sixth Form: Lunar Dispersing Mist.”
Even when their blades clashed, he felt a shift in mood. The wind breather was out to kill him now, and his slashes became much more aggressive. His bloodlust was stronger too. He was an experienced demon slayer, and Muichiro knew that if he didn’t take this seriously, if he hesitated even for a moment, this wind breather could, and would, kill him.
Between their blades clashing and Kokushibo’s blade clashing against the stone breather’s weapons, the once still air was humming to their battle. The floor had splintered. The pillars had cracks running up their structure. Some had even shattered. It was a chaotic battlefield, where it was impossible to take one’s attention off their opponent, yet from the corner of his eyes, Muichiro spotted the fallen slayer eating a piece of Kokushibo’s hair.
That was the opening the wind breather needed. Muichiro ducked, but blood was already pouring out of his neck. The only good news was that the blade didn’t cut all the way through.
“Why?!” the wind breather screamed. “WHY IS IT ONLY KAMADO’S SISTER? WHY IS SHE THE ONLY ONE ABLE TO RESIST THIS?” Angry tears ran down his face, but his face only contained rage.
Kamado? That name sounded so familiar, like a ray of sunlight in a cold winter.
“Kamado Tanjiro,” Muichiro blurted out. He remembers that name. He remembers a kind voice and an even kinder smile.
“Yes.” There was a new hope in the wind breather’s eyes. “Tokito, do you remember Kamado?”
Yes, he did. Or more accurately, he remembers parts of him. He remembered the way this Tanjiro made him feel. He felt a sharp migraine as he tried to remember this person. He was someone important to Muichiro, and he wished he could remember better.
From his end of the battlefield, Kokushibo called out, “Focus, Muichiro-kun. He’s trying to distract you.”
Muichiro looked at his ancestor. That dark red hair and the hexagonal pattern on his kimono that could be mistaken for squares at certain angles. A face appeared, one with a flame-like scar and burgundy eyes. Kamada Tanjiro. His friend. The person who he flew paper airplanes with.
Muichiro lowered his blade. The wind breather, Shinazugawa, took a sigh of relief. But just as quickly, a voice, Muzan’s voice, sounded in his head.
“Defeat the wind breather. He’s keeping your dear friend Kamado away from you. If you don’t defeat him, he’s going to kill Kamado.”
“He wouldn’t,” Muichiro argued back, but he was already fading from consciousness. He tried to grip onto his last remaining piece of humanity, but it was slipping fast out of reach.
“Oh, but he would. Just look at that rage in his eyes. He hates demons, and he hates Kamado for protecting a demon. If you don’t kill him now, he’s going to kill Kamado. So kill him.”
Muichiro wasn’t even thinking when he suddenly found his sword stabbed into Shinazugawa’s chest. He took out his blade, but it was too late, the scent of marechi hung heavily in the air. Any humanity fighting back immediately lost as the scent of the intoxicating blood filled Muichiro’s nose. His focus became fuzzy. His grip on his sword loosened. It dropped to the floor with a muffled clang. Any logical thought vanished from his brain as he could only think of devouring the wind breather standing before him.
He saw his form tense as he got ready to strike him down. Muichiro didn't care. He wanted to taste that blood, so he edged closer to the wind breather with no regard for his safety. He saw the sword coming towards him and only managed to dodge at the last second. He was drooling for the wind breather’s blood. He wanted that blood. He needed that blood.
“Blood Demon Art.”
It was impossible. He shouldn’t have been able to use his blood demon art. Not in this state. Especially not for his first time when he hadn’t even eaten a human yet. By some miracle, his blood demon art manifested, and now, the entire room was covered in mist. The mist covered him completely, including his bloodlust, yet to him, he could see everyone within the mist as clear as a cloudless sky.
The wind breather had no clue Muichiro was right behind him until he felt a searing pain in his shoulder. He tried to shake Muichiro off, but Muichiro was clamping down hard, drinking up his blood as an alcoholic would with sake. The taste sent Muichiro into a frenzy. He wanted more. He needed more.
“Muichiro.”
He’ll deal with that later.
“Muichiro!”
He felt small hands wrap around his waist. He stopped drinking yet kept his hands firmly on the wind breather, though it was rather unnecessary since he had already fainted from the blood loss. Muichiro looked down and found a face identical to his but much younger staring up at him.
“Muichiro, stop. You’re going to kill him if you continue.” He looked angry, but he held no malice.
“Who are you? My younger self coming to haunt me?” Muichiro stared down judgementally at the kid.
“I’m your older brother, you idiot!”
Muichiro looked down at him, unimpressed. “I don’t recall having an older brother.”
The kid’s eyes tightened. His jaw clenched. He now looked sad, yet Muichiro could see frustration behind those eyes.
“Muichiro, I want to see you again, so please. Please don’t kill him. Please remember.” His face was now buried in Muichiro’s side. Hot tears soaked through his shirt. “Remember, the Mui in Muichiro stands for infinity. You have infinite potential. Infinite strength. Use that strength and fight back. Show me you’re still human.”
Muichiro wanted to get rid of the child. He wanted to crush him, but when his hand raised to strike, somewhere, deep in his consciousness, his humanity stopped him. His humanity was climbing out of the void with determination. He tried to push his humanity back down, turning the dark void into mist so that he couldn't climb out. He didn't want to be the reason why they fail. But even if his humanity couldn’t grip onto anything solid, he used his brother’s voice as a safety line. Yuichiro's voice might have been faint, but it was the most solid and real thing in the darkness. He’ll get back to his brother and get rid of the monster he’s become.
“Muichiro. Do not forget about Kamado. You must finish the wind breather and–”
“You think I’m a fool?” Muichiro huffed. He had to focus hard to keep his humanity from falling back. “I’d say you almost had me, but it was Shinazugawa’s blood that drove me crazy. But you were right about one thing. I will help Tanjiro-kun, but to do that, I need to defeat Upper Moon 1. So goodbye, you good for nothing demon king, who can’t even keep control over his own demons.”
With that one final pull, he took control over his body again. His brother was no longer there, but Muichiro knew he was still watching in case he needed to bring Muichiro back to his senses. He looked down at Shinazugawa. He was still alive, thank goodness. Even with all the blood Muichiro drank, he was certain Shinazugawa would recover.
Which meant his next order of business was taking care of Kokushibo. He activated his blood demon art. Mist emitted from his body. He grabbed Genya’s gun and placed it in front of him. Genya looked at him with wide eyes, and Muichiro gave him a stiff nod in return. He then advanced towards Kokushibo, gripping his sword as tightly as he could, turning the blade red.
“Genya-kun, shoot!” Muichiro yelled, dispersing the mist so that Genya had a clear shot.
Two bullets lodged in Kokushibo’s chest, but his attention was turned solely on Muichiro.
“So, you fought against that man's blood. I’m impressed yet disappointed.”
Even though he spoke calmly, he seemed agitated. Like something was irritating him. The reason showed itself in seconds as a large tree sprouted from Kokushibo’s body. He was immobilised. Muichiro took that as his opportunity to decapitate him. As a demon, he was faster, and with his blood demon art being able to conceal him, it was a flawless strike. But as soon as he let go of his blood demon art, his head rolled off his shoulders.
When did he strike him? It didn't matter since Kokushibo would disintegrate too. He held onto his head, trying to make it stick back to his neck, but the skin where Muichiro’s red blade hit began to disintegrate. Muichiro himself was disintegrating, but he was satisfied and at peace. He had kept his humanity and defeated Kokushibo. That was all he needed to rest easy.
“Tokito-kun, thank you,” Himejima said softly. Muichiro saw his giant form kneel beside him. "For someone so young, you fought well. Without you, we wouldn't have survived. You have my deepest respect."
“How’s Genya-kun?”
“Alive,” Himejima replied without skipping a beat.
Muichiro could rest easy.