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The agony of his charred flesh seeped deep into Muzan's bones as he fled the battlefield, the barely-living bodies of the Pillars trailing not far behind. His once-superhuman stamina had dwindled to that of an ordinary human.
In the end, he had managed to kill the majority of his opponents, though some Pillars still remained, barely clinging to life. He wanted to annihilate them all, but the poison coursing through his body and the rising sun made it an impossible task.
Muzan heard Kamado Tanjiro's frantic screams echoing behind him as he made a run for it, the sun setting slowly in the sky.
"Come back here, you wretched coward!" The red haired boy shrieked, his throat raspy and swollen.
But Muzan didn't stop. Honor, an obligation for foolish men with no regard for their lives, he thought, wanting to roll his eyes but refraining as, one lapse of judgment would surely lead to his demise.
So, Muzan Kibutsuji, the former demon king, ran like a coward, lunging at one of the demon slayers and without any reservations gnashing his teeth into their frontal lobe.
He would need a fair amount of energy to run.
A couple of projectiles flew his way, and one managed to hit his ear, cleanly ripping it off.
Although they were extremely fast for human beings, they were still too slow. And the demon had managed to slip away. He disappeared into the still dark woods, soon to be brightened by the sunlight. He needed to find shelter.
Thankfully, it wasn't long until Muzan had managed to find a small, actively deteriorating cabin in the middle of the woods. The wooden building was practically falling apart, it's walls full of holes from which a light day began to slowly creep in.
Muzan cursed, If any of those slayers catch up to me, It's going to be over.
He shook his head, it's going to be fine, I'll kill all of them before they can do anything.
As he pondered those words, a sharp, stabbing pain pierced his insides, sending shockwaves through his entire body. Right. The poison. Kibutsuji clutches one of his remaining hearts and felt it pulsating in a strange, irregular manner.
It hurt so badly, about comparable with the excruciating pain that he endured just minutes earlier, the sun burning each layer of his skin.
His insides tingled, and Muzan felt them shift involuntarily—his intestines writhing within his bowels. The sticky, unsettling sensation echoed in his ears, making him wish he could tear himself apart just to be free of the torment.
Kibutsuji's nails grew in length as he gripped the creaky floor, breaking it apart with his claws. Muzan stifled a groan as best he could, still paranoid that demon slayers might be stalking him in the shadows.
Just as he closed his eyes, Muzan felt a presence entering a cabin...only it wasn't a hostile one. The demon slowly brought his head up, his long white hair blocking his line of vision.
"Muzan-Sama?" Kibutsuji breathed a sight of relief as a familiar voice of Kokushibo's reverberated throughout the cabin.
Looking up, Muzan saw the tall silhouette of a man. He wore black pants, but his upper body was bare, with fleshy horns violently sticking out of his skin, blood trickling from the holes they pierced to pass through. His face was obscured by a white cloth, though one could still see the grotesque black and red horns that protruded from his forehead.
"So, you made it out alive after all. I lost contact with you halfway through the battle. I assumed you had perished, Kokushibo," Muzan addressed the man in an uncharacteristically soft tone.
"It felt like death was staring me in the face by the end of the battle," Kokushibo admitted as he stepped further into the cabin, the sunlight now shining around them.
Another wave of nausea hit Muzan, twisting his insides and sending him stumbling backward, his back slamming against the cabin wall. "I'm glad you survived," Muzan said, watching as Kokushibo faltered, nearly tumbling to the ground at his words.
"The feeling is very much mutual," Kokushibo replied, settling onto the dusty hardwood floor.
A momentary silence settled between them as Muzan struggled to suppress the symptoms of the poison. For all he knew, it wouldn't kill him—just strip him of his power, reducing him to the strength of an upper rank demon.
He cursed under his breath. Perhaps death would be preferable to this humiliation.
Furthermore, though the poison could not end him, it would take centuries for his body to regenerate, and even then, he would likely only regain 30% of his original power. Muzan wasn’t entirely sure he would get the chance, with the Demon Slayer Corps surely rummaging through the forest in search of them.
"Are you doing well, Muzan-Sama?" Kokushibos deep voice pierced through the constant ringing in Muzans ears, snapping him back to reality.
Kibutsuji raised his head, his vision blurring as he made an effort to search for Kokushibo's figure.
"It's nothing but mild annoyance." He managed to say.
Only, it was the last thing that left his mouth before the demon was knocked unconscious—his body fighting against itself.
Your death is nearing, Muzan Kibutsuji. I will drag you to hell with me. Tamayo's snickering laughter echoed in his skull.
The boy is too weak, it'd be better to just let him go. He's a humiliation for our family.
Everyone knew he was born cursed, our poor baby taken away in death and replaces by...this.
You hear this, Kibutsuji? Is your life flashing in front of your eyes?
He snapped awake, swiftly pulling himself off the floor as the panic settled in his bones. What kind of demented nightmare was that?
The light was stronger now, the orange hues in the sky signalling late afternoon, when the sun's rays were at their peak. Shifting his attention, he noticed Kokushibo sitting on the opposite side of the cabin, his body as still as stone.
"How long was I out?" Muzan muttered, flipping the white hair off his face, the strands catching on the grotesque mouths sprouting from his pale body.
"A couple of hours. It's hard to tell exactly," Kokushibo replied, turning his head slightly to glance at Muzan.
Kibutsuji sighed. Despite the fact that his senses were still sluggish, he sharpened his hearing, straining to pick up the faintest sounds of footsteps.
"No one has found our location, though a few came close," Kokushibo added.
"I see. That's good."
Kokushibo shifted slightly in his seat. "If I may ask, do you have any plans for escape? The entire area is surrounded by the Pillars, and your condition is deteriorating by the second." He shook his head. "What I mean is, are you well enough to fight or flee, Muzan-Sama?"
Muzan couldn’t help but roll his eyes at Kokushibo’s words—the use of honorifics sparked an unexpected sense of shame within him. After all, did he still deserve to be called them, in his current pathetic state, brought on only by his own incompetence? It was a bitter reminder of how he had failed to take humans seriously, even after 500 years.
Muzan bit his lips, the spark of irritation gnawing at him. "Just drop it." He said, causing Kokushibo to send him a deeply confused look.
"The honorifics I mean, we're hiding out in a dirty cabin, there's no need for that at the moment."
Kokushibo remained motionless, and even if Muzan couldn't see his face, he felt the fluttering disarray of Kokushibo's mind.
"I understand... Muzan."
Now that Kokushibo had said those words, Muzan couldn’t shake the feeling that something was missing at the end of his sentence. Of course, he quickly brushed the thought aside.
"To answer your question, yes, I do have a plan. I have a loyal demon in Osaka who will undoubtedly provide us a safe place to recuperate. His ability is somewhat similar to Nakime's, though marginally less effective."
"And as to the question of my condition. I could fight of course, only I... Worry that could impact my condition even more as the poison seems to grow in strength particularly when I exert myself. Our best strategy is to quietly slip away I believe."
Kokushibo didn't answer him, barely nodding.
Once more, a stifling silence settled between them. As Muzan reflected on their nearly 500 years together, he realized they had never truly conversed casually. Kibutsuji usually preferred it that way, as finding companionship and getting closer with others was something he perceived as wholly human.
And humanity was far beneath him.
Only, in that exact moment, he found himself feeling uneasy, desiring to speak up and possibly find comfort in this quiet stillness of the moment.
It must be a product of my terrible condition, he mused.
Still, he decided to be the one who reaches out, crossing the unspoken boundary set between them oh so long ago.
"Why the mask?" His tone casual, as if discussing something utterly mundane
Kokishibo turned toward him, clearly surprised by the question, "During my fight with the Pillars, my psychical form...changed." His inflection fell on the last word.
"That makes both of us." Kibutsuji impatiently replied, brushing his long hair off his face, dried blood clinging to his fingertips, "Now, why the mask?"
The demon remained silent for a moment before slowly beginning to fidget with his hands, "I wouldn't want to disturb you with my deformed appearance."
"Disturb? I assure you a couple of teeth, won't frighten me." Muzan replied flatly, nodding toward the mouths scattered across his body, their glistening teeth reflecting the sunlight.
Without another word, Muzan propped himself up and took off walking towards Kokushibo, making the man visibly uncomfortable in the least as he stopped in front of him. With the few wobbly steps, Muzan knelt in front of him sharpening his gaze as he stared at the white cloth.
Then, Muzan paused for a moment before extending his hand to grasp the edge of the material.
But as he tried to pull it up, Kokushibo's hand shot out, halting Muzan's movements. "I really don't think that's necessary." Though he attempted to maintain a facade of confidence, an unmistakable insecurity crept into Kokushibo's voice.
"I think it is. You're sitting here with your face covered while I'm not even wearing any clothes—how is that fair?" Muzan stated in a monotone voice. His words prompted Kokushibo to almost jump back, as if he had just realized Muzan’s nudity.
Kokushibo glanced around hurriedly, seemingly searching for something to offer the demon king to clothe himself with.
"I don't have any reproductive organs either way, why does that matter?"
Kokushibo dropped his head, "It's... a custom." That was all he could say.
In his startled state, Kokushibo hadn't had time to catch Muzan's hand before it reached him. Gently, he lifted the sheet up, revealing the deformed face of the demon.
His face, once defined by sharp edges, had been deformed into a blobby mess, his mouth and cheeks lined with an array of sharp teeth. A pink sack of flesh hung from the sides of his face, obscuring what would have been his ears, from which long horns sprouted, each ending in a single, scorpion-like spike. They pulsated rhythmically, the veins bulging beneath the surface.
The once-aligned six eyes were now scattered across his face, some stretched more to one side than the others.
Overall, it was a macabre sight for anyone else.
Anyone but Kibutsuji.
As he held Kokushibo's chin, cupping it gently with his hand, Muzan couldn't help but feel a tinge of fascination. Kokushibo's flesh felt extremely soft beneath his fingers, almost meaty. He definitely had the urge to bite into the tender skin covering the man's face and rip away a chunk, just to experience how it would feel.
But alas, he suppressed his urges, "It's not terrible," He said, bringing Kokushibo closer to have a better look, "It's not even bad."
Kokushibo's expression quivered, eyes averting Kibutsuji's gaze, "It's...inhuman."
"So are we, it's about time you come to terms with it." Kokushibo didn't seem to like that answer as his jaw tensed up.
Muzan sighed, "If you're really upset, then we can do something about it. Not now of course as we're both on a brink of collapse, but after a time of healing we can just... fix your form back to normal." He said, reluctantly letting go off Kokushibo's jaw and moving back to the other side of the room.
Kokushibo kept quiet, observing Muzan's moves, with his face visible he looked much more uncomfortable.
"Your hair," He began, his voice almost breaking, "It suits you."
"Does it?"
"It's different, but not in a bad way."Muzan could've sworn he saw a faint flush of red pass through Kokushibo’s cheeks, though it was hard to tell with the many teeth embedded in his face.
"I'm not a big fan of having long hair," Muzan said, grabbing a fistful of his own. "It reminds me of worse times."
"Worse times?"
Kibutuji shook his head, "Back when I was a human. But it's pointless to speak about such sentiments any longer."
An uncomfortable feeling settled in Muzan's stomach—he was sharing more personal information than he preferred. Yet, at the same time, with each sentence that left his mouth, he felt a small part of the darkness in his heart lift ever so slightly.
Kokushibo's eyes wandered to the side, "I understand... Nevertheless, my opinion remains unchanged."
"Maybe I'd like them more if they didn’t get stuck in my teeth," Kibutsuji muttered, tearing a chunk of his hair from the mouth embedded in his shoulder.
"You've never cut your hair, have you?"
"No, there's a belief that a samurai should never cut his hair. It's part of the tradition," Kokushibo responded calmly.
A tradition? A human tradition? Kibutsuji tried to speak, but a sudden cluster headache struck him with full force. The sharp ringing in his ears muffled all of his senses, and his heart pounded as if trying to burst through his chest. A foul taste surged from the pit of his stomach, crawling up his throat, nearly causing him to vomit.
Fucking poison.
As he struggled, a presence appeared beside him, kneeling to assess Muzan's condition. Kibutsuji reached out, his hand gripping the man's strong bicep, squeezing tightly in an attempt to steady himself. Closing his eyes, he began counting backwards from ten, each number completed by a deep, calming breath.
By the time he finished, Muzan felt more at ease, though the excruciating pain that engulfed his entire body had yet to dissipate.
"Are you sure it's nothing?"
Muzan shook his head, "It won't kill me."
Kokushibo grunted in response, "Will sharing my blood help?" he asked, extending his arm toward Muzan.
Muzan paused to consider the offer, but quickly shook his head again. "Probably not. Your blood is much weaker than mine, even under these conditions. Besides, you've been poisoned by a crimson blade, haven't you?"
Kokushibo’s eyes widened, surprised by Muzan’s words. "Indeed... I had forgotten. My apologies."
"No need for that," Muzan replied, dismissing the concern. "Just make sure you fully regenerate as well, and we'll be fine."
Kokushibo silently acknowledged Muzan's request, stepping back slightly. To Kibutsuji’s surprise, however, he remained on the same side of the home, still within Muzan’s reach. Was he concerned about Muzan's condition?
The thought unexpectedly made Muzan feel more at ease.
Kibutsuji only needed a few minutes—or so it felt—to collect himself. Leaning back against the wall, he rested his head, beads of sweat trailing down his face. Each droplet was swallowed by one of the grotesque mouths embedded in his body, a sensation that only deepened his disgust.
How far had he fallen, to the point of hiding himself away like this? No... he had already dwelled on that thought too much today. He needed to stop pitying himself and focus on what lay ahead.
At that exact moment, his senses were stirred awake as he registered a pair of footsteps approaching their destination. Looking over, he noticed Kokushibo on guard as well, his hand resting on the hilt of his sword.
They remained still as stone, listening in to the noise of footsteps until-
The men went the other direction, away from the cabin.
Muzan was close to exhaling a sigh of relief, but he paused midway through, his senses still worried about the person next door turning around.
They stayed silent for an unusually long time—far longer than necessary— until Kokushibo finally broke the stillness. "It won't be much longer until the sun sets, and we can begin our journey toward Osaka. Do you know the exact directions we'll be taking?"
"It’s hard to tell while we’re in the middle of the woods, but there’s a distinct road that leads there. I’ll recognize it once we get out," Muzan assured him. "I’m not entirely sure of where we are as of now—Nakime’s ability dropped us in an unfamiliar place—but I am confident we can manage. I am familiar with Japan’s roads like the back of my hand."
Kokushibo nodded his head, deciding to trust Muzan's words.
Indeed, it wasn’t long before the sun-drenched area was enveloped in a blanket of darkness, allowing the demons to emerge from their degrading hiding place.
The soft glow of the impending night filtered through the darkened woods, illuminating a path that would lead them out of the forest.
Only, just as Muzan had turned around, he heard a sound of shuffling behind him stop. Looking back, he was met with Kokushibo staring in the opposite direction—his mind swirling in turmoil.
"If I may," Kokushibo began, his voice firm. "I'm not the kind of person to run away. During the fight with the Pillars, even after having my head smashed, I didn’t give up and I defeated my foes. Hiding from the sunlight is already enough of a humiliation in my eyes. Running away from a bunch of weaklings is just insulting."
Muzan, leisurely scratching his skin, responded without much concern. "If you want to go back and fight them, you're more than welcome to do so. You would likely defeat them all and claim victory. However, while we’ve been hiding from the sun, the surviving Pillars have also been recovering their strength."
He paused, his tone steady. "I don’t question your abilities, but with your body still fighting off the crimson blade’s poison and the Pillars preparing for another battle, it’s very possible that victory could come at the cost of total paralysis—or, though unlikely, death."
Kokushibo’s expression faltered. "But running away is…"
"Dishonorable?" Muzan interrupted, his tone sharp. "If I’m being honest, Kokushibo, I thought you threw that notion away centuries ago when you accepted my offer and bent the knee. Yet, even as a demon, you cling to your humanity."
Muzan leaned forward, his voice dripping with condescension. "You don’t indulge in the slaughter of humans like the others, always thinking yourself better than the rest of the Upper Moons, more civilized." He let out a snarky laugh, not bothering to hide his disdain.
"There’s no need for that anymore. Just let go," Muzan said, extending his hand toward Kokushibo. "It won’t be hard to make the same right choice twice, Michikatsu."
Kokushibo's whole body jerked back at the long forgotten name being spoken aloud. He stared at Muzan, each of the six red eyes faltering, their gaze softening with each second.
Until Kokushibo breathed out a low groan.
"If we start our march now, we should be in Osaka by morning, at most..." He said with a resigned tone, moving closer to Muzan.
Good choice. He thought.
"No need to worry, I don’t intend to spend another day in this decrepit house that’s actively falling apart," Muzan assured Kokushibo, retracting his outstretched hand before turning his back to him.
The night ahead was shaping up to be extremely long.