"I'm sure even someone like you can appreciate the irony in this situation."

Tanjirou didn't respond to the man - or rather, he couldn't respond because he was a little preoccupied with the excruciating pain coursing through his body. He screamed as he convulsed. It hurt, it hurt more than when he had broken his bone as a child, it hurt more than when the man stabbed his hand through Tanjirou's stomach and rearranged his innards, it hurt it hurt it hurt.

"It's impolite to not respond, you know," the man said conversationally.

Tanjirou let out another agonizing scream, so loud his throat bled. He felt hot, as if he was burning up with a fatal fever. Sweat drenched his entire form. It burned. His mind could barely even form a coherent thought, much less verbalize a response.

"Okay, seriously though," the man frowned. "It shouldn't hurt that badly. Why are you having such an adverse reaction to the demonization process?"

The pain was too much. Tanjirou fell unconscious, the overwhelming pain shutting down his mind.

"... and now he passed out. Of course he did." The man sighed. "Disappointing. This trip was disappointing. To think that his descendants would be reduced to this..." He shrugged. "Oh well."

Humming a cheerful tune, Kibutsuji Muzan stepped out of the small home. He briefly considered burning the home to the ground just for the extra bit of irony, but decided not to in the end. He was a generous man, after all. The boy and his sister, when awoken, would be hungry, and cooked human meat always did taste so terrible.

And they say he wasn't considerate.


Tanjirou was hungry.

Even before he regained consciousness, his body was already aware of that. He woke up with saliva pooling in his mouth and an overwhelming urge to eat. A delicious smell drifted to his sensitive nose, a smell so rich and sweet it nearly caused him to whimper. It was like a drug, causing everything else to fade from his mind. Only hunger, and the smell, remained.

Where was it coming from? Where was the source of the smell?

Sweeping his gaze around the small, dark room, Tanjirou caught sight of his brothers' mangled, bloodied corpse. His sisters' bodies, ripped to pieces, lay on the ground next to his mother, who was staring into the air with sightless eyes still wide with fear.

The smell was coming from them.

Tanjirou was still for a moment.

Then he took a step forward, his primal instincts taking over. They smelled delicious. He wanted to eat them, to drink their blood and sink his teeth into their soft flesh.

It wasn't until he had already knelt down next to his mother, saliva dripping from his mouth, that he realized his eyes were wet.

Crying? Why was he crying when there was such delicious food in front of him?

Because they're your family.

Tanjirou staggered back as his mind miraculously returned to him. Everything flooded back - the man, the pain, the death of his family.

His eyes went wide as he realized what had just transpired. Had he just tried to eat his own family? His mother, his brothers, his sisters... He nearly threw up at the thought. His hunger still remained, compelling him to devour their bodies, but he refused. He had to control himself. With all his willpower, he suppressed his hunger, pushing it to the back of his mind.

Oh gods. Tears streamed down Tanjirou's face. They were dead. They were dead. Hanako. Shigeru. Takeo. Nezuko. Rokuta. His mother. The man had killed them all, killed the people he loved the most on this earth.

He screamed, a sound of pure agony and sorrow.

"I'm sorry! I'm sorry I couldn't protect us, I'm sorry I couldn't save us, I'm sorry I'm sorry I'm sorry!" He repeated the words desperately, hoping with all his might that his mother would tell him that it's okay, that his siblings would hug him and reassure him that it's all right. But no. No amount of apologies could bring his family back.

Tanjirou sobbed, scrunching his eyes close in pain, unable to bear the sight of his dead family any longer. "Please," he begged. "Please - "

He froze when he heard the sound of shuffling. He glanced up, looking around the room before gasping out loud. He could've sworn he just saw Nezuko shift slightly. Was his imagination playing cruel tricks on his mind?

Slowly, Nezuko pushed herself to her feet and stood up.

Tanjirou stared at her, not daring to believe his eyes. "N-Nezuko?" he whispered.

Then the dam broke.

"Nezuko!" Tanjirou rushed forward, hugging her tightly. "You're alive. You're - "

He paused as he felt something wet on his shoulder. For a moment he panicked, thinking Nezuko was about to bleed out in his arms, but after pulling back and examining the situation, his heart dropped.

Nezuko was salivating, looking past him and at their family's bodies on the ground. At a closer glance, Tanjirou could see that her appearance had changed slightly. Her eyes were now a vivid pink color, her skin was paler than before, and she had fangs. The tips of her hair had turned red-orange. More importantly... her scent had also changed. She smelled like him. Different. Not necessarily bad, just fundamentally different, as if they were no longer human...


Tanjirou absently recalled what the old man had told him. Could it be true?

He was broken out of his thoughts when Nezuko attempted to push past him, presumably in an attempt to eat their family.

Without any hesitation, Tanjirou hugged her again, albeit a hug meant to restrain. Nezuko growled, first trying to push him back, then, when she failed, she began ripping through his skin with her nails while biting down on his shoulder, hard. Tanjirou winced, but this pain was nothing compared to the pain of losing his family. He endured, murmuring soothing words to Nezuko in an attempt to calm her down.

"Please, Nezuko. They're our family. They're our family. Don't eat them. Don't let the hunger control you. Fight it! Don't give in! I know you can. Come back to me."

His words didn't seem to get through to her. She struggled, trying to break free.

"Nezuko, please," Tanjirou whispered desperately. "You're the only family I have left. I..." his voice broke.

"I can't lose you too."

Nezuko abruptly stopped struggling, her entire body tensing up as if some revelation had just struck her before she relaxed completely, going limp in his arms.

Tanjirou slowly pulled back from the hug, careful to keep himself between Nezuko and their family in case she was trying to trick him.

She wasn't. The tears in her eyes told him that much.

"Oh gods... Nezuko," and Tanjirou was hugging her again, comforting her. Even though she was trembling badly, she didn't sob or make any noise.

Was... was she trying to be strong? For him?

Tanjirou himself teared up, emotions suddenly overwhelming his mind as the full reality of their situation hit him. "We'll... we'll figure something out," he promised. "We'll be alright, Nezuko. Don't worry. We'll be alright. I swear it - " he finally registered the blood on her forehead. "Nezuko!" he pulled back and looked at her concernedly. "Are you okay? Is the blood yours? Are you hurt?"

Nezuko didn't respond and slowly, Tanjirou began to realize that something was wrong.

"Nezuko? Talk to me, Nezuko. Are you okay? Does anything hurt?"

No response. She just stared at him uncomprehendingly, tears still in her eyes, as if she couldn't fully process his words.

"This... may be a problem."

As much as Tanjirou hated it, he couldn't bury his family just yet. Nezuko was top priority. He had to find out what happened to her, why she seems to have lost all rationality and coherency. He needed to talk to Saburo, the only person who had ever mentioned demons before. The only person who might know what happened to them.

But... demons don't exist. They can't exist. They're just stories told to frighten children. Right?

Tanjirou got a sinking feeling. The same sinking feeling that came along with the realization that even though Nezuko had clawed and bit his skin, it didn't hurt at all. He touched his shoulder just to confirm what he already knew.

His wounds had already healed.



The moment they stepped out the door into the frigid cold, Tanjirou became acutely aware of just how hot he was. He was burning up. It was like a fever, only he had none of the chills and only the heat. It didn't hurt, though.

They began running, Tanjirou practically dragging Nezuko along. He tried to ignore how they were both faster than before, or that even though they were sprinting, they weren't growing tired. There was no point dwelling on it. The hunger was still there, but now that they were away from all the blood, it became easier to control.

Soon, they reached a familiar small cottage. Tanjirou wasted no time, immediately pounding loudly on the door. "Saburo! Are you in there? Saburo! It's Tanjirou and Nezuko! I need your help! Please, I'm sorry for bothering you right now, but open the door - "

The door opened. "What do you want?" Saburo asked blearily, wiping his eyes. "Do you have any idea what time it is-?"

The old man fell silent when he got a good look at them. "Ah. Demons." He hesitated for a moment, eyes flickering back into his house before a look of resignation passed over his face. Then a steely look entered his eyes and he nodded determinedly, as if he made up his mind on something. "Please, if you're going to kill me, do me a favor and exit those disguises. First off all, they're really bad. Borderline laughable. Nobody over the age of three would be fooled by them. Second, I'd rather not gaze upon Tanjirou's face as you eat me alive. I'm pretty fond of the kid, you see."

Tanjirou blinked, unsure of how to respond. "Err..."

"What, were you expecting me to scream and run? Cry a little?" Saburo raised an eyebrow. "I'm much too old to outrun a demon, and I don't have anything in my house that can hurt you two. If I'm going to die, then I'm going to go down with honor - "

"Saburo! It's me, Kamado Tanjirou!" Tanjirou cut in.

Saburo scoffed. "Right. I'm old, not blind."

"No, really! I really am Kamado Tanjirou!"



"Prove it," Saburo challenged. "Answer my questions correctly."

Tanjirou nodded. Saburo asked him several questions before frowning heavily when Tanjirou answered them all correctly.

"Now do you believe me?"

"There's always the possibility that you tortured the answers out of the kid, or you're possessing him right now - "

"Demon," Tanjirou whispered.

Saburo stared at him cautiously. "Yes. That's... what you are. The claws and fangs are kind of a dead giveaway."

"No, I mean..." Tanjirou shook his head disbelievingly, staggering back. "We're demons. Genuine, man-eating demons. I... I just realized."

His eyes suddenly widened before he quickly bowed. "I'm sorry, Saburo, for waking you up from your sleep. Thank you for your time. Nezuko, let's go."

"Wait," Saburo called confusedly as Tanjirou and Nezuko turned around and began walking away. They paused, looking back at the old man. "Why are you leaving?"

Tanjirou was silent for a moment. Then he spoke in a low, nearly inaudible voice, "We're... hungry. I... don't want to accidentally hurt you."

Saburo stared at him incredulously. Then, when he saw that Tanjirou was being completely sincere, his stare slowly morphed into a look of horrified realization.

"... oh gods. You're actually Tanjirou, aren't you."

Tanjirou nodded wordlessly.

Saburo hesitated for a long moment before he swallowed audibly and said, "Come in. Let's get you warm."

Tanjirou backed away, shaking his head frantically. "I can't! I might accidentally hurt you. I shouldn't have even come here."

"You're restraining yourself right now, aren't you? And besides, you have no intentions to eat me, correct?"

"Well, yes, but - "

Saburo nodded. "That's good enough for me. Come in."

"But - "

"Tanjirou. Trust me."

Tanjirou hesitated before relenting. "Fine. Just... stay far away from us."


"So you're saying that you two were attacked by a man who turned you both into demons and brutally murdered the rest of your family?" Saburo looked pale.

Tanjirou nodded from where he was sitting.

Saburo grimaced, rubbing his face. "Tanjirou, there are no words in this world that can express how sorry I am." He paused. "For what it's worth, I would hug you, but..." he trailed off meaningfully.

Tanjirou understood, nodding. "It's best if you keep your distance. I - " he choked back a sob.

"I almost ate my mother," he confessed quietly. "She was lying on the ground and she smelled so good and I just wanted to devour her - " he clenched his fists so tightly his sharp claws dug into his skin and drew blood.

"But you didn't." the old man said simply. "You managed to do the impossible and control yourself. Well done, Tanjirou."

"But how? Why am I normal while Nezuko is unable to even speak?"

"Why are you abnormal is the question you should be asking. From what little I know, demons are evil monsters who have no mercy or remorse. Their minds are lost, and they indiscriminately murder and eat humans. You, Tanjirou, are not normal. Nezuko is more like a demon than you are."

They both cast their gazes at Nezuko. She was sitting silently as they talked, blank eyes staring off into the distance. She decidedly did not look like an evil monster who had lost her mind.

"And even she's not normal," Saburo amended.

"How? How are we like this?"

Saburo shrugged. "No idea. Ask the demon hunters."

"The people who kill demons," Tanjirou recalled the story. "Do you think they can help us?"

Saburo shrugged again. "Tanjirou, I've only heard of them in passing. When they saved me from the rampaging demon, I was already unconscious. I don't know anything about them other than that they kill demons..." He paused. "On second thought, you probably shouldn't go anywhere near them."

"But we're peaceful!" Tanjirou protested. "We haven't hurt anyone, and we never will. I'm sure they'll understand if we explained it - "

"Don't!" the old man said harshly. "If you walk up to one and introduce yourself as a demon, expect to be killed on sight. I doubt they have an 'ask questions first, shoot later' policy."

"Fine," Tanjirou said grudgingly. "Do you know how to turn a demon back into a human?"

"I don't. I don't know if it even can be done." Saburo turned away. "I'm sorry, Tanjirou."

A heavy silence descended over them.

"Then I'll find a way," Tanjirou finally said.

The old man frowned. "Excuse me?"

Tanjirou looked at him, determination blazing in his eyes. "If there's no way to turn demons back into humans, then I'll find a way. I'll turn Nezuko back into a human, no matter what," he vowed.

Saburo looked taken aback, but then he nodded. "Then if you're going to do that, I have two pieces of advice for you. One: avoid the sunlight. Demons don't venture out into the daylight for a reason. Two: you have to grow strong."

"Grow strong?" he asked confusedly.

The old man sighed, suddenly looking very tired. "Grow strong because if you don't, then you will die. You can't turn Nezuko back into a human if you're dead."

He gazed into Tanjirou's eyes. "Everyone is against you now. The humans will hate you because you're a demon, and the demons will hate you because you refuse to eat humans and wish to turn back into one. You exist in two worlds. A demon who still lives like a human. You understand me?"

"Y-Yeah," Tanjirou nodded, even as his heart sank at the thought. "I do."

Saburo sighed, lighting his pipe. A thin line of smoke drifted upwards. They sat there in silence for a few moments, each lost in their own thoughts.

"It'll be dawn soon," Saburo said suddenly. "If you need to go anywhere, now is the time, before the sun comes up."

Tanjirou nodded, standing up and bowing low. "Thank you," he said sincerely.

"You're welcome."

Saburo sat there smoking his pipe, watching the Kamado siblings walk towards the door. "Tanjirou," he said. "If you ever find yourself about to kill and devour an innocent human... I hope there will still be enough humanity left in you for you to kill yourself instead."

Nezuko reacted for the first time since meeting him, whirling around and growling at him, baring her fangs. Her entire body had tensed up, and her pupils had dilated into slits.

"Nezuko, it's fine," Tanjirou murmured, placing a calming hand on her shoulder, before saying in a louder voice. "I understand. Saburo, we will never hurt humans. I swear it."

The old man let out a puff of smoke. "I believe you. Good luck, Tanjirou."


Tanjirou knew it was risky being out in the day, but it was cloudy enough that he wasn't very worried. It was worth the risk.

Five graves. In about an hour, Tanjirou had dug five graves and buried his family. The sorrow and sadness he felt physically hurt, and he struggled to not break down into tears every few minutes. Nezuko watched from inside their house, an impassive expression on her face. Tanjirou's heart broke thinking about how Nezuko may not even recognize their family anymore.

He had just finished praying when a man burst out of nowhere, dropping from the sky, his sword aimed to cut off Tanjirou's head. Tanjirou's eyes widened as he quickly dodged to the side, narrowly avoiding certain death. He jumped back, putting some distance between himself and the man.

"Who are you?" Tanjirou stared at the man with no small amount of fear in his eyes.

The man stared back. Spiky black hair pulled back into a ponytail. Dark blue eyes that contained no traces of mercy. "Why did you bury them?"


The man gestured at the five graves. "Why did you bury them? Are you trying to save your meal for later?"

"Wha - No! I buried them because they're my family!"

The man narrowed his eyes. "They're your - " he was cut off when Nezuko charged out the house, her pupils dilated into slits.

"Nezuko, no!" Tanjirou barely managed to stop her, grabbing her arm and holding her back. "You can't! He'll kill you!"

Nezuko growled, straining to break free.

"What do you mean by they're your family?" the man asked calmly, ignoring her.

"They're my family! My mother and brothers and sisters!"

The man tilted his head. "You're a demon. You both are."

"We're not!" Tanjirou paused. "Well, we are, but we've never hurt humans before."

"Do you seriously expect me to believe that?" the man asked dryly.

"It's true, I swear!" Fear shot through Tanjirou when the man took a step forward. "How could we hurt anyone if we just got turned into demons last night?"

The man stopped. "You were a human yesterday?"

Tanjirou nodded, tears welling up in his eyes despite himself. "I was. Me and Nezuko were both humans. And my family... Hanako. Shigeru. Takeo. Rokuta. Mother. They were still all alive. But a man attacked us. He murdered my family, leaving me and Nezuko alive, only..."

"Only you became demons," the man finished, his voice soft. "I see."

Tanjirou brightened. "You do? You believe us?"


Instantly, the man was in front of Tanjirou. Tanjirou froze up against his will, his muscles locking in place. He didn't even see the man move.

"I'll kill you before you lose what shreds of your humanity you still have left."

His blade blurred - and met flesh. Nezuko screamed in pain as the blade sliced through her wrist. However, that slowed the momentum of the blade, allowing Tanjirou to quickly recover his wits and kick the man as hard as he could.

The man grunted, leaping back.

Tanjirou ignored him, however, instead staring at Nezuko's bleeding wrist with wide eyes. It was a stump, her hand having been cut clean off. She had blocked the strike with her own body to protect him.


A crashing wave of unbridled madness overwhelmed his mind. The world around him faded until only one thought remained, a thought that filled Tanjirou with a rage he had never felt before.

This man just hurt the only family Tanjirou has left.

No. Not just that.

This man is trying to kill the only family Tanjirou has left.


Tanjirou roared, and the constant heat within him exploded.


Tomioka Giyuu eyed the demons warily. He hadn't anticipated the girl blocking his strike with her own arm. In fact, if he hadn't seen it with his own eyes, he wouldn't have believed it.

A demon protecting another by using their own body as a shield? It was unthinkable.

Furthermore, a new demon should be starved and insane, incapable of any rational thought. And yet, that clearly wasn't the case with this boy. He had buried his family's bodies. He recalled his past life, and judging by how the girl had protected him, she probably did too, albeit to a lesser degree.

Even now, with a limb cut off, the girl should've gone berserk. However, she just stood there growling, glaring at him with pink eyes, making no moves to attack.

These two demons were anomalies.

As Giyuu pondered on this, the demon boy roared in rage, an inhuman sound escaping his throat.

Immediately, Giyuu got the sense that something was wrong. It took him only a second to realize what it was.

The snow around the boy had melted.


Where was the boy?

His instincts screamed at him, and only years of training saved him. He raised his sword as the boy blurred in front of him, his hand shooting forward to pierce Giyuu's chest, claws glinting dangerously. Giyuu barely managed to block the boy's attack, staggering back from the force of the blow. Simultaneously, he heard several loud cracks.

However, in that single strike, Giyuu already knew. He had won.

While the boy was fast and strong, his movements were rough and unpolished. Now that the element of surprise has been taken away and Giyuu was prepared for his speed, it was impossible for the boy to win. Skill would always reign supreme over brute strength.

On top of that... Judging by the loud cracks Giyuu heard when the boy's hand impacted with his sword, the boy had likely broken several bones in his hand.

An inexperienced, weak, newborn demon. He stood no chance against the Water Pillar.

Or so Giyuu thought.

Incredibly, as Giyuu weaved through attacks, the boy was somehow keeping up with him, snarling all the way. It was almost as if he was reading Giyuu's movements and predicting what he would do next.

The gap in their skill was immeasurable, and yet Giyuu was unable to land a single blow on the boy.

However, the boy couldn't break through Giyuu's flawless defense either. He telegraphed all his attacks, making it a simple matter for Giyuu to counter them effortlessly. It was like fighting a child - which, in a way, was true.

Giyuu jumped back, regarding the demon boy with dull blue eyes.

"I'm sorry."

Then he stopped holding back.

This entire time, he had been trying to kill the boy with the Fifth Form: Blessed Rain After a Drought, an attack that kills the target painlessly. Giyuu didn't use any other Forms out of mercy. After all, he owed this boy. If he had just gotten here half a day faster, he could've saved the boy's family. However it's apparent that the demon wouldn't go down easily, so he has no choice but to utilize the other Forms.

Oh well. There was a reason why the Fifth Form was only supposed to be used when the demon surrenders.

In a burst of speed, he appeared right in front of the boy.

Total Concentration. Water Breathing. Third Form. Flowing Dance.

To his credit, the demon actually managed to react in time, a feat countless demons couldn't even hope to replicate. He snarled, trying to move backwards to get out the range of the swing, but he was too slow, and he knew it.

In the instant before death, the anger and rage vanished completely from the demon's visage. Emotions flickered across his face. Sadness. Sorrow. Regret. Whatever madness had afflicted the demon disappeared entirely, and Giyuu knew instinctively that when the boy's head fell to the ground, he wouldn't die as a demon, but rather a human -

Giyuu's eyes widened slightly.

The sadness and regret clouding the boy's face suddenly cleared up, revealing soft pink eyes that were impossibly kind.

Eyes that reminded him of Sabito.

Warm, gentle eyes that made Giyuu feel like home.

Damn it.

Mere centimeters away from the demon's neck, the sword halted in place.

Giyuu gave a mental sigh. He must be getting soft, because he was seriously considering letting the boy and his sister live.

The concept of sparing demons should be anathema to him, a Pillar. And yet, nothing had ever felt so right before.

"You've never eaten a human?" he asked again, just to be sure.

The boy, who had frozen up, immediately nodded. "We never have, and we never will hurt another human."

Giyuu regarded him. He saw the sincerity and truth in the boy's gaze.

Sabito. What would you do?

After only a moment of hesitation, Tomioka Giyuu, the current Water Pillar, sheathed his sword.

"What is your name?"

"W-what?" The boy looked lost.

Giyuu paused. "Do you remember your name?"

"T-Tanjirou. Kamado Tanjirou. Wait, aren't you going to kill me?"

"Are you going to hurt another human?"


"Then no." Giyuu walked forward. The boy backed up fearfully before Giyuu's words fully registered in his mind.

"N-no? You're going to let us live?" Hope shone in Tanjirou's gaze.

Giyuu nodded wordlessly before turning to the girl. "Can you speak?"

She growled at him.

"She can't," Tanjirou answered for her. "She's my little sister, Nezuko, but for some reason - " Then he caught sight of Nezuko's wrist and panic flashed across his face. "Her hand! You cut off her hand!"

Giyuu knelt down on the ground and picked up Nezuko's hand, ignoring Tanjirou's yelp. "Here," he offered it to Nezuko.

Nezuko stared at the appendage before looking up at Giyuu.

"It's easier to reattach limbs than fully regenerate it," he explained.

Nezuko hesitated before she tentatively reached out, keeping her eyes on him. He didn't move, so she quickly took her hand and held it to her wrist. It instantly began healing, bones fusing , muscles reattaching, and the skin stitching itself back together. Tanjirou stared with wide eyes.

"I can't leave you here," Giyuu said suddenly.

At the boy's confused look, he elaborated. "If you kill another human, then it will be my fault. I cannot allow you to remain here. But at the same time, I cannot take you with me either. Any other demon slayer would kill you on sight, regardless of whether or not you've hurt a human before."

Except for one, Giyuu remembered. That might work...

"Then what will you do?" The look of fear was back on the boy's face.

Giyuu tilted his head. "I'll have to ask Oyakata-sama," he mumbled to himself. "Perhaps Shinobu would take you in..."

"There's no need."

Instantly, Giyuu whirled to the side, unsheathing his sword in one smooth motion.

An old man stood next to him. White haired tide back in a ponytail that framed milky eyes. A blank, emotionless expression on his face. A strange mark on his forehead. A sheathed sword hung at his hip.

Giyuu hadn't sensed him at all.

"Who are you?" he demanded.

The man looked at him. "Good morning. My name is irrelevant. Just know that I will take in these two siblings."

"Are you a demon slayer?" Giyuu questioned.

"I was," came the short answer. "Not anymore."

Giyuu narrowed his eyes. "Even if I do entrust these two demons to you, how do I know you'll be strong enough to stop them if they go onto a rampage?"

The man regarded him impassively, his entire posture relaxed.

In retrospect, Giyuu shouldn't have blinked. Stare-offs were for amateurs, and dry eyeballs would only hinder him in a fight. However, in the literal blink of the eye, the man had somehow moved right in front of him, his sword held to Giyuu's throat.

"Rest assured," the man murmured. "My skills are more than adequate enough to incapacitate these two."

"Point taken," Giyuu replied calmly, mentally preparing himself to use Lull just in case this man actually decided to attack. At such a close range, it would be difficult but not impossible to deflect the damage.

The man tilted his head. "Your movements and breathing have changed," he observed. "A defensive form? However, they don't match any existing forms in Breath of Water. A completely original technique, perhaps?"

Giyuu's blood went cold. How? How had this man known?

"No matter. You won't need it." The man slowly lowered his blade, not making any sudden moves. "I apologize for my rudeness. Please, forgive me."

"Who are you?" Giyuu asked again.

"As I have said, my name is irrelevant. I will take care of these two children. I give you my word."

Giyuu hesitated. On one hand, he shouldn't be trusting random strangers he just met. However, this man was clearly a human. And he was strong, far stronger than Giyuu himself. He could handle himself against two newborn demons.

And besides... Giyuu got the feeling that the man wasn't exactly giving him a choice.

"Very well." Giyuu sheathed his own sword. "Then I entrust these two demons to you."

"Thank you," the man responded politely.

Logically, Giyuu knew this was a bad decision. He should at least ask Oyakata-sama first. However...


He left the two siblings and the ancient man, his intuition and heart telling him that he made the right choice.


Tanjirou looked at the old man after the demon slayer had left. "T-Thank you for your help," he bowed. "My name is Kamado Tanjirou, and this is my little sister Nezuko."

"I know."

"You do?" Tanjirou asked confusedly. "How? I've never seen you before."

The man regarded him silently. Tanjirou shifted uncomfortably under his milky stare.

"You are a demon, and yet you retain your sense of self," the man finally said, apparently ignoring his question entirely. "The same with your sister. Two demons who swear never to hurt humans..."

He chuckled as a small, nearly imperceptible smile spread across his lips. "You truly are his descendant."

"What?" Tanjirou frowned at the man's cryptic words. The man ignored him again.

"Tell me, Tanjirou. Do you wish to grow strong?" he asked.

Tanjirou thought about how easy it had been for the demon slayer to defeat him. How weak he had been. How he had utterly failed to protect Nezuko. His reply was immediate.

"I do."

The man nodded, as if he had expected the answer. "It will not be an easy path," he warned. "You will face countless obstacles. Demons with more power than you can ever imagine. Humans who will hate you simply for what you are. So tell me, Tanjirou. What are you willing to do?"

Tanjirou stared back at the man, flames of determination roaring to life in his unflinching eyes. "Anything," he promised in an unwavering tone. "For Nezuko, I'll do anything."

The man smiled contentedly. "Good. From this day forth, I shall be your master."

Tanjirou nodded slowly. "Okay... But who are you?"

However, even as Tanjirou asked the question, he already instinctively knew the answer. A forgotten memory that was not his surfaced to his mind. The old man's name was -

"Tsugikuni. Yoriichi Tsugikuni."


So, umm... I've been told by Master Yoriichi that I should keep a journal. So here it is. Sorry if my handwriting is bad - my arms and wrists and hands hurt. They're trembling so badly, it's like they're leaves in a storm. But this pain in my arms must be nothing compared to what you had to go through when you shielded me from certain death. Don't worry. I'm training now to make sure you'll never have to experience such pain ever again. No matter what.

I'm worried about you, Nezuko. When you couldn't wake up that day, a raw panic filled me and I almost lost control of myself. I already lost our father and mother and brothers and sisters. I couldn't lose you too.

Thankfully, Master Yoriichi assured me that you would be alright. He said something about your body adapting and evolving, and how you needed to conserve energy by sleeping. I don't know why I'm not the same.

I miss you. It hurts, how much I miss you. Come back to me, Nezuko.


I had dodge training today to sharpen my instincts.

Everything hurts.

I don't think I like dodge training very much.


Nezuko! You won't believe what I learned today! Did you know that the Dance of the Fire God is actually the Breath of the Sun? I can't believe it!

Since I already know all the movements, all I need to do now is learn how to breathe properly. I wonder what Master Yoriichi meant by that...


My lungs hurt. My lungs hurt so much. I'm so tired. My body aches all over. I had to breathe into a gigantic gourd and make it explode using my breath alone. It took me such a long time, but I finally managed it.

I'm sorry Nezuko, but it looks like today will be a short entry. I can already feel my eyes slipping shut...


Wake up. Please just wake up. Wake up, Nezuko. Please.


I've noticed it before, but Master Yoriichi doesn't smile very often. Or frown. Or show any emotions at all, really.

But even if he doesn't outwardly display any emotion, I can still smell how he feels.

Master Yoriichi is sad. The scent of sadness constantly clings to him. Something devastating must've happened to him for him to feel this way.

But it's fine. Even if Master Yoriichi is sad all the time, I'll be happy for the both of us.


I did it! I finally landed a single blow on Master Yoriichi! I mean, sure, he had both hands tied behind his back and he was blindfolded and it was just a graze against the fabric of his haori, but I still did it!

Of course, he thoroughly pummeled me afterwards just to ensure I wouldn't get a big head. But I'm still so happy!


My speed, stamina, and strength have increased so much since I began. I'm strong now, Nezuko. I'm strong enough to protect you.

So please wake up.

I'm begging you.

Wake up.


I'm about to undergo the Final Test. Master Yoriichi says that if I pass this test, then he will allow me to leave and go search for a cure.

Isn't that wonderful? I can finally go find a way to turn you back into a human again!

I'm a little apprehensive about the Final Test, though. What will he do?

Oh well. No sense in obsessing over the what-ifs. Whatever it is, I'll do my best and succeed.


Tanjirou entered the clearing with a cheerful smile. "Master Yoriichi!" he greeted. "What is the Final Test-?"

His breath caught in his throat.

Yoriichi was standing in the middle of the clearing, towering trees surrounding him. It was snowing, just like the day Tanjirou and Nezuko were turned into demons. The night air was crisp and fresh, and the moon cast a silver glow over the snow on the ground.

In the moonlight, Tanjirou saw Nezuko laying on the ground behind Yoriichi.

The old man held his sword to her throat.

"Master Yoriichi," Tanjirou said slowly, carefully. "Can you... please not let your blade go anywhere near Nezuko?"

"I didn't teach you everything," Yoriichi said calmly.

Tanjirou froze. "What?"

"There is a Thirteenth Form in the Breath of the Sun. The ultimate Form, the culmination of all my skill and mastery. It is the most powerful attack in existence. With it, defeat is impossible for the user."

"Okay... what does that have to do with Nezuko?" Tanjirou slowly drew his own black blade that Yoriichi had given to him.

"I will only teach the Thirteenth Form to you if Nezuko is dead."

For a moment, Tanjirou thought he was dreaming. Or having a nightmare. However, this was real.

"W-what?" he gasped out.

"Emotional attachments do nothing but make you weak," Yoriichi said in a voice devoid of emotion. "The only way you can truly become strong is if you break the bonds that hold you back."

Tanjirou forced a nervous laugh. "You're joking, right?"

"I'm dead serious." Yoriichi's reply silenced Tanjirou. "If you desire power, if you desire to be the strongest, then you have no choice but to let Nezuko die. With the Thirteenth Form, none will be able to stand up to you. You will gain unparalleled power." He lowered his blade so that it was touching Nezuko's neck. "Just give me the word. I'll make it quick and painless, I promise."

Tanjirou clenched his fists. "Master Yoriichi, please," he begged. "Don't do this. I don't want to learn the Thirteenth Form."

Yoriichi tilted his head. "I don't believe you."

He raised his blade above Nezuko's sleeping body before swinging down -

Tanjirou moved.

He breathed sharply as desperation drove him forward. He moved faster than he ever had before, pushing his body to the absolute limit. In a split second, he entered striking range.

Breath of the Sun, Sixth Form. Burning Sun.

He unleashed a circular slash that deflected Yoriichi's blade, the force knocking him back slightly. Tanjirou immediately pressed the attack, all his concentration devoted on keeping Yoriichi away from Nezuko. Yoriichi was forced backwards from the sheer force of Tanjirou's strikes.

The snow underneath their feet melted from the heat they emitted as shockwaves shook the ground. Tanjirou breathed, shifting seamlessly from form to form, his eyes focused intensely.

Time lost all meaning as they fought. To any onlooker, they would be nothing but a blur of movement. Hundreds of blows were exchanged in the span of a few seconds. Desperation was etched on Tanjirou's face, but also a grim determination. Failure was unacceptable here.

"Why do you continue to fight me?" Yoriichi inquired, tilting his head to the side to dodge a stab. "You are far too weak. You have no hope of ever defeating me."

"I... Don't... Care! I still have to try!" Tanjirou hissed in pain as Yoriichi's blade sliced his stomach, leaving a nasty gash. "I can't just give up and let you kill her!"

"Even if you would gain unmatched power that made you the strongest in the land?" Unlike before, there was a strange, fiery intensity in his eyes that Tanjirou had never seen before.

"Even then! After all, who cares about having unmatched power... if there's nobody left to protect with it?!"

Yoriichi's eyes widened as his movements faltered slightly.

Tanjirou instantly took advantage of the opening and unleashed his attack.

Breath of the Sun, Ninth Form.

The Setting Sun.

A downward slash with a flaming blade that contained all of Tanjirou's strength, his desperation, his willpower, his desire to protect Nezuko. The fastest, most flawless attack he had ever performed.

Yoriichi looked down at the huge diagonal gash on his chest. A fatal blow. Blood slowly stained his clothing.

Tanjirou stared at him, trembling, falling into a defensive stance. Then his eyes widened as he saw something completely unexpected.

Yoriichi was smiling. Not his normal small, barely noticeable smile, but rather a bright beam of joy and happiness.

"Well... done, Tanjirou. You passed my Final Test."

Confusion was clear on Tanjirou's face. "What?"

Yoriichi coughed, flecks of blood falling to the ground "I'm sorry, Tanjirou. It was a selfish test, meant only for my own peace of mind. Putting you through it was cruel. I'm sorry. But I had to be sure. Please, forgive me."

"What do you mean?"

There was a moment of silence.

"I had an older brother once." Yoriichi's eyes glazed over, lost in memories. "I loved him with all my heart. He always said that he wanted to be the strongest samurai in the land, so I decided to follow his dream and become the second strongest samurai."

"Oh." Tanjirou paused before asking, "What happened to him?"

Yoriichi's eyes flashed with pain. "He willingly became a demon and killed countless innocents with the same skills I had taught him. He betrayed me in his own pursuit of power. All he ever wanted was to be the strongest, regardless of the cost. And that was why I gave you this Final Test."

His gaze turned sad. Regretful. "I couldn't permit myself to make the same mistake as before. I could never forgive myself if I taught you my techniques, taught you how to kill, only for you to turn it back on innocent lives. It was selfish and cruel of me. I'm sorry."

Yoriichi smiled widely again. "Tanjirou, when you fight, don't fight for revenge or hatred. It will only consume you. Instead, fight to protect your sister. Fight for Nezuko. Don't ever lose your kindness."

Tanjirou took a hesitant step forward. "Y-Yoriichi."

"Oh, and one more thing. You already know the Thirteenth Form. You knew it all along. Use it to do what I could not all those years ago and kill Kibutsuji Muzan, the man who murdered your family."

Yoriichi coughed again. His kimono was now completely soaked with his blood. "Goodbye, Tanjirou. When I see you and your sister again, I sincerely hope we will meet as humans." He gave one last smile as bright and brilliant as the sun itself. A smile he could never form in life. "I believe in you."

"Master Yoriichi - " Tanjirou took another step forward but then stopped.

He was all alone in the clearing.

Tsukiguni Yoriichi was gone.

For one long moment, Tanjirou didn't say anything as he absorbed Yoriichi's words. Then, softly, he spoke.

"I forgive you."

He was unable to tear his eyes away from the spot where Yoriichi had stood. He had lost yet another person in his life. His dear master - no. Yoriichi was not just his master.

He was family.

Tanjirou knelt down and prayed, closing his eyes.

Then he snapped his eyes back open as he felt a warm, comforting hand on his shoulder. His breath hitched as he whirled around.

His eyes widened before filling with tears once more.

Nezuko was standing there, her head tilted head adorably to the side.

"Nezuko. You're... awake," He breathed in shock, hesitant to make a move.

Nezuko had no such reservations. She reached out with her small arms and drew Tanjirou into a tight hug. In her warm embrace, he let all his worries and concerns melt away, relaxing completely. Tears streamed down his face as he hugged her back tightly, breathing in her comforting, familiar scent.

He was home.


This will be my last journal entry. I'm writing this as you sleep. In the future, when you're a human again, we can read these together.

Before the Final Test, Master Yoriichi told me to seek out a demon named Tamayo. She's a demon that broke free from Kibutsuji Muzan's control. She'll know how to cure you.

She has to.

We'll leave tomorrow. Traveling will be difficult since we can only travel at night, but we'll manage it. I'm sure we can.

I can't wait until you're a human again!

Kimetsu no Yaiba is undoubtedly one of my favorite series. I only watched the anime and read the manga relatively recently, and it was breathtaking. The music, the godlike animation by Ufotable, the plot and characters... It was amazing. Naturally, I had to write some fanfiction about it.

For once, I already have the ships decided. It should be pretty obvious what they are as the story progresses.

Thank you all for reading, and please review!