Chapter Text

Chapter 1: Aftermath

“Muzan-sama… that man appears to be a swordsman…” She spoke to the Demon Progenitor who was walking a few steps ahead of her. A sharp turn of his head and the harsh and violent look he always directed at her, made her lower her head. The message was clear. 

‘Do not speak until given the permission to do so.’

Tamayo stayed silent, pulling y/n back slightly, while subtly sneering at Muzan, trying to shield the demoness from the Progenitor. She lifted her gaze, her eyes landing on the swordsman approaching the trio. Glimpse of a pitiful look appeared in her gaze, having seen it all multiple times now. She was worried about another innocent life being taken in the hands of the Progenitor.

Muzan stood staring at the swordsman, the two facing each other standing at a distance. It was silent for a long time, and while Muzan had a confident, cocky smile on his face, the swordsman looked determined, resolute.

It was evident to both y/n and Tamayo, that the man had only approached them for one purpose — to kill the Progenitor of Demons.

“I am no longer interested in swordsmen who use breathing.” Muzan commented calmly, his smile turning into a sly smirk, before disappearing entirely. He had snapped. Why wouldn’t he? A mere swordsman thought he could kill him? The Demon Progenitor? The strongest being alive? The thought was laughable, to say the least.

The swordsman didn't respond, his hand simply resting on the hilt of his katana, gaze never falling astray. Though he briefly glanced at the two presences behind Muzan, his observation fell short.

In an instant, Muzan’s arms contorted, his flesh twisting and mangling under the kimono sleeves, transforming into long flesh appendages, bearing multiple mouth-like structures, fangs protruding from his skin, covered in black marks which spread through the appendages. Tamayo held her breath, and so did y/n, though both for completely different reasons. 

The two female demons watched, frozen in their places due to the power differences, as Muzan’s long ranged and inhumanely-fast attacks reached the swordsman, as fast as a whip. And even when the distance between the two was so great, bamboo split behind the swordsman, fortunately for the young man had dodged Muzan’s attacks.

The look which flickered in the human’s eyes was readable, as he was struck with a realisation. One wrong move, one miscalculation, and even the slightest hit of Muzan’s attacks would cost him his life. And Muzan's grin widened at the state of the one before him.

But what was to come, was something neither Muzan, y/n, or Tamayo had expected. In the next moment, the swordsman moved in a perfect rhythm almost as if performing dance moves with the katana in his hand, the attack almost as brutal, or even more, than Muzan’s own. 

Aimed towards his vitals, which Muzan didn’t know the swordsman could see, the progenitor was frozen in place when he felt the pain from the blade, as if he was being burnt by the scorching sun itself.

The katana pierced and sliced through Muzan’s body smoothly, blood spraying out as the appendages emerging from his arms were cut off, along with his left leg, and the one that shocked him the most, his neck.

y/n took a subconscious step forward, worry and distress consuming her, witnessing what was happened to Muzan. How the odds were turning against them.

She was ready to call out the Progenitor’s name and activate her blood demon art and charge towards the swordsman. But her actions were interrupted as Tamayo abruptly pulled her back, covering y/n’s mouth.

“Don’t be reckless…” She reminded, earning a reluctant nod from y/n. Tamayo’s eyes were shining with a hopeful glint that the filthy man of a Progenitor would finally be killed. He deserved it, she knew, for ruining her life, for turning her into a monster.

Despite outwardly agreeing to Tamayo’s words, the worry in y/n’s heart only grew, her gaze fixed on Muzan’s back. She couldn’t show strong reactions to such a predicament for various reasons. Some of them being – Muzan snapping or getting angry at her for showing weakness, and the fact that her actions might give out a possible vulnerability to the swordsman, and furthermore to the organisation he could’ve been associated with.

Muzan was on the ground, his severed arms holding his decapitated head, preventing it from falling. His eyes were wide, annoyance boiling up in his head, frustrated by the lack of regeneration in his body.  Something was wrong, the demon realised, for it had been the first time ever since he felt such excruciating pain, affected by someone’s attacks.

A measly swordsman’s attack. A single one at that.

“What is the value of a life to you?” The swordsman asked Muzan, looking down at the stunned demon, whose face instantly grew red with rage, veins popping over his arms, face, and neck. He didn’t respond, snapping at the thought that an ordinary swordsman had managed to almost kill him.

Muzan’s continued silence made the young man move once again, determined to get rid of the Progenitor once and for all.

But he halted at the sound of Muzan’s teeth grinding against each other, the enamel almost shattering by the force of the friction. The swordsman was surprised, watching how Muzan's body burst and divided into multiple pieces of flesh, the chunks exploding in all directions.

The swordsman instantly moved, realising Muzan's attempt at escape. He swung his katana frantically, determined to put an end to the Demon Progenitor. But could only manage to get rid of more than half of what Muzan’s body exploded into.

Tamayo was shocked, her heart breaking as she saw how Muzan had managed to escape. ‘He overcame it…’ she realised, disheartened at how it would be so much harder to actually kill Muzan now that he was able to survive a decapitated head. 

y/n, however, was more focused on looking for Muzan, her demon senses allowing her to follow one of the flesh chunks which had managed to escape the swordsman’s katana. And she ran after it, determined to find her lord again.

And unfortunately for Tamayo, and the swordsman, named Yoriichi…

…the 300 flesh chunks that escaped Yoriichi’s blade, enough for the size of a head when combined together, were enough for Muzan to survive. Albeit barely.

.

.

.

It had been hours since y/n had been running, her heightened senses working tirelessly, trying to search for Muzan’s presence in the thick and vast forest.

The sun was close to rising, yet she hadn't been able to find a single clue about the Progenitor’s whereabouts. The zori sandals she had been wearing had long fallen from her feet after running, the white tabi socks now-dirty and loose at her feet.

It was much harder to find Muzan, since his presence couldn’t be felt in the demoness’ mind, and when it did, it was extremely subtle, faint, not enough to get a slightest hint on his whereabouts. It only increased her worry, the circumstances and silence all pointing to one thing: Muzan was very weak, wherever he was.

The sky had begun to brighten slowly, indicating the arrival of dawn. She knew if she spent another thirty minutes or more searching for Muzan, she would end up dead. y/n surely didn't want to leave the world before checking on Muzan.

So she sped up in her tracks, running as fast as she could to seek shelter in a nearby shack or cave.

That’s when she felt a flicker of pulsating throb in her head.

Muzan was nearby.

She looked around, gaze raking around the dense trees, before she spotted a small cave at the foot of the mountain nearby. The sun was rising, she had to go seek shelter there, whether or not Muzan was present.

But as she neared the mouth of the cave, the heightened sense of smell she possessed confirmed the doubt, her worries quelling in an instant. Her pace got faster, reaching the cave just in time. Thankfully, the sun was still below the horizon.

Slowing down, she made her way deeper in the cave, eyes desperately searching for that one despicable and filthy man she was so in love with.

That’s when she heard shifting, the sound of squirming and squelching. A disgustingly wet sound of flesh and what not. She followed those noises, and a shuddering breath surfaced from her throat, her eyes widening at the sight before her.

She was on her knees the next moment, holding onto the, thankfully alive, remnants of her lord’s presence. Muzan was nothing more than a ball of flesh, hardly the size of a human head. The smaller chunks squashed and moulded together like a ball of clay, with throbbing green and purple nerves, some even pulsing out from the surface of the thin skin.

She saw how the twisted sections of Muzan’s still-developing vertebral column broke through his skin, like a snake coiled around an egg, with blood gushing out from the gaps left between his mangled form.

“Mu… Muzan-sama…” She softly called out, her emotions overtaking any fear she had of that man, as her thumbs rubbed soothing and gentle circles on the mass of flesh. He wasn’t regenerating.

Was that swordsman really so strong that…

No. She couldn’t think that. Muzan would make it. He was the strongest being alive. There was no doubt he would make it…

A long time passed as y/n held Muzan on her lap, her arms wrapped around his fleshy form. She knew the demon lord was displeased to say the least, as the mass of muscles and tissues resisted and squirmed against her arms. Though his resistance didn’t stop y/n from tightening her grip on him.

Her emotions had overridden every other thought that could’ve possibly appeared in her mind.

Night had fallen once again, one entire day had been spent with futile attempts of finding ways to accelerate Muzan’s recovery. A sigh escaped her lips, her gaze falling on Muzan’s still form. He wasn't dead, she knew, feeling faint pulsing of blood beneath the skin.

It appeared he was asleep. After all, resisting and constantly squirming only exhausted energy unnecessarily. The best course of action was to be in a comatose state, so the body and cells focus only on recovering.

Her relaxation was short lived, when she heard the crunch of dry leaves, the sound originating from the mouth of the cave. She was on alert in an instant, ready to defend Muzan and attack any potential threats. But before she could move, a calmly deep voice rang out, stopping her.

“Don’t fret… y/n-sama. It is just… me, Kokushibo.”

Kokushibo, the samurai and heir to the Tsugikuni clan was the latest addition to the demonkind. Formally a human named Michikatsu, he left behind his two sons and wife for the pursuit of power, after resentment and jealousy towards his younger brother had taken root inside his heart.

Stopping right in front of y/n, who was holding Muzan, Kokushibo knelt down. Holding out the severed head of a human man, he addressed slowly.

“Muzan-sama… I–”

“Shh… he’s asleep, Kokushibo.” y/n interjected softly, her voice lowered into a whisper. It earned a nod of acknowledgement from the addressed demon, before he presented the severed head to her.

y/n’s  gaze shifted from Kokushibo to the decapitated head he was holding. “Is that…”

Kokushibo nodded in response before the female demon could complete the question, placing the severed human head at y/n’s feet. He shifted back on his haunches, before reporting in a whisper.

“Yes… y/n-sama… I have successfully… eliminated the Corps’ Leader… Ubuyashiki has been taken… care of, as per Muzan-sama’s… orders.”

The two sat in a comfortable silence for a while, Kokushibo brooding over Muzan’s state, while y/n sharing the same worries as the male demon. But then, she thought about how she couldn’t just spend her entire time worrying. A plan had to be devised, one to speed up Muzan’s recovery.

“Let’s feed this head to… Muzan-sama…” She broke the silence, looking at Kokushibo, continuing once their gaze met each other’s. At least he was willing to listen. “For now.. Let’s feed this to him.. somehow. We must gather as many humans as possible…”

“Are you implying… a mass slaughter, y/n-sama…?”

And as the confirmation from y/n was set in Kokushibo’s mind, the two demons undertook the responsibility to get as much food as possible for Muzan’s speedy recovery.

Masses of clans and villages were slaughtered, uncountable demon slayer encounters were faced head-on by Kokushibo as a consequence, while y/n took it in her own hands to deliver the vital organs and then somehow feed Muzan.

The demoness also spent hours posing as a fellow human in a far away village, helping a doctor just for the sake of learning to make various medicines and usage of herbs, hoping to formulate an elixir that had some healing properties helpful to Muzan.

Months passed, with the two demons having to change locations multiple times to subdue suspicion, and to not give away Muzan’s location in such a fragile state.

Muzan’s recovery was extremely slow considering his usual strength and regeneration, with the attacks from Yoriichi’s sword having affected him exactly like the sun’s rays, as if his cells had burnt off permanently.

But y/n and Kokushibo's efforts weren’t entirely in vain, for after constantly working to provide food stock and medications for over 10 months, Muzan had healed enough for him to use all of his five senses.

His regeneration was much better than the initial days, and the only signs of the unpleasant confrontation with Yoriichi were the permanent scars left all over his body, and the temporary tweaks in his appearance and stature. 

Currently taking shelter in a small dwelling in the outskirts of a town, Muzan was in his room, resting with a glass of blood obtained from a human that Kokushibo had brought home, while y/n was applying a herbal embrocation to his scars, hoping to soothe Muzan’s skin externally.

“Muzan-sama…”

“Hm?”

“Pardon the discourtesy… but, it seems the humans Kokushibo brings aren't enough. You’re still–”

“I am not weak." Muzan cut her off mid-sentence, "Don’t you dare insinuate such nonsense, y/n.” He gave a harsh look to her, almost murderous, making y/n lower her gaze.

He wasn’t weak, not in the slightest. His gaze turned sharper, staring down at his companion. He had half the mind to punch her head away right at the moment, but he tamed his expression.

“But, my lord, it’ll take much longer for you to recover at this rate—” y/n tried to reason her worries to Muzan, knowing very well his vulnerable situation could be taken advantage of by the enemies.

But Muzan had had enough, raising his arm to land a harsh slap on y/n’s face, making her fall to the side, the concoction staining the tatami mats. “If you wish to continue displaying such insolence in my presence, then get out. Right this instant.”

Knowing better than to provoke Muzan further, especially after he had gotten violent, y/n slowly nodded. Pushing herself up to stand, the pinkish-red bruise forming on her cheek, as she made her way out of the room, closing the shoji doors behind her.

"I should've been more attentive to the words I used…" The demoness murmured to herself, turning around to lean against the shoji door, her eyes landing on the full moon in the sky, shining bright as if mocking her predicament. Nonetheless, she trudged her way towards the edge of the engawa, taking a seat, with the pebbles crunching under her zori sandals.

She couldn't help her thoughts from running to the past, connecting the similarities from back then. She didn't dwell on it much. After all, she didn't want to risk her sour mood making things worse for Muzan, in case he allowed her back inside.

Her chain of thoughts was broken when she heard footsteps approaching the dwellings where they currently resided in. Growing alert, she shifted her entire focus on the footsteps, her enhanced hearing abilities trying to decipher the nature of the presence that was steadily drawing closer — human or demon.

y/n's distress increased tenfold once the sound of footsteps halted abruptly, everything going eerily silent for a moment. Her fingers twitched, the cells in her body vibrating with clear intents of unleashing her blood demon art.

But before she could proceed with that, a gust of wind flew past her, dust hitting her face, making her press her eyes shut. And that's when she heard a voice behind herself.

"y/n-sama… it seems my arrival scared you…"

"Oh.. Kokushibo..." y/n let out a miffed sigh, rubbing her forehead as she turned to look at the six-eyed demon, standing straight as a log with blood-soaked sac, looking right back at her with uncoordinated blinks from his multiple eyes. "You did more than just 'scare' me."

"I apologise…"

"It's alright. Did you bring the food-stock?" y/n inquired the demon, to which she received a nod. Lowering his head as if seeking permission, Kokushibo took a step forward, walking past y/n with intentions to deliver the humans for Muzan to consume.

But a voice stopped him, right before the demon's hand touched the handle to the shoji door.

"He wishes to be left in solitude, for now. It's best to respect his wishes."

Stepping back without a word of argument, Kokushibo placed the bag aside against the wall, before turning around to face the female demon. And after he had ushered y/n t take a seat at the engawa once again, he knelt down at her feet on the gravel, looking up at her before breaking the silence. "May I ask what happened…?"

"Well…" And with a sheepish smile, and the nervous fidget of her fingers on her lap, y/n answered. "You know how he is. He loves his space and solitude, and absolutely no interruptions, haha."

Kokushibo knew better than to believe the woman in meekly sitting in front of him, especially with the bruise clearly visible on her cheek, but he couldn't just bluntly point it out to her.

He didn't want to displease his Master.

Instead, he opted to approach the topic evasively, slowly. He wasn't stupid enough to do so right at the moment.

"How far has Muzan-sama's recovery progressed, y/n-sama?"

"It has been… slow. The humans, no matter how many we bring, aren't sufficient for a speedy recovery."

Kokushibo wordlessly listened as y/n presented him with the reality of the situation. "I brought those ones having that rare blood. Won't those humans be more effective, y/n-sama? You said Muzan-sama showed a significant spike in health after consuming those."

"You're right… Kokushibo. But remember, his patience isn't long-lasting, especially when it's related to weaknesses. He wishes for a solution much faster and efficient than those rare-blooded humans."

They both sighed, before a tense silence replaced the atmosphere. Kokushibo could feel it, something in y/n's demeanour, how she was obviously refraining from speaking up. Or perhaps was hesitant. It had been like this for weeks, and the demon figured it was time for a confrontation.

"There's something you wish to say, don't you y/n-sama?"

Another long silence followed, with Kokushibo expectantly looking at the demoness, his six eyes blinking in an eerily coordinated manner. With a defeated drop of her head, y/n broke the silence. Her feet mindlessly kicking the gravel, as if trying to ground herself while speaking of this heavy topic.

"I've been trying to get something to happen… but the opportunity doesn't arise easily."

"What opportunity, y/n-sama…?"

"…Trying to get Muzan-sama to consume me, Kokushibo."