Yuko Nishimura had approached Soma while wearing the mask of admiration, pretending she did not mind that he was a demon, and while loudly condemning other swordsmen for treating his identity as a demon as something special.
Then, without the slightest hesitation, she plunged the vial of medicine — the one created through the joint efforts of Tamayo and Shinobu that could turn a demon into a human — straight into Soma's body.
"Every demon deserves to die. They all deserve to die! My family, my father, my mother, my grandfather… every single one of them died at the hands of demons."
"How can this world allow something as disgusting as you to exist?"
At this moment, Yuko Nishimura's eyes were filled with nothing but hatred for demons — a twisted, all-consuming hatred.
Feeling the needle pierce his body and sensing the girl's overwhelming hatred directed at him, Soma still found it difficult to understand.
It is normal to hate demons when your own happiness has been destroyed by one. But the demon that killed your family and ruined your happiness was not me. Why must you place that sin on my shoulders?
"Because you are a demon!"
Yuko lifted her head, her voice sharp and shrill. "You can never change the fact that you are a demon."
Soma fell silent for a long while before speaking in a low voice.
"So the evil deeds I have never committed, I must bear because I am a demon. The sins I have never committed are forced upon me simply because of my identity as a demon. Is that what you are saying?"
He looked at the girl in front of him, his voice still calm.
"No," Yuko shook her head.
"Then why? Clearly, I am not the root of any of these sins. Clearly, the root of all sin has always been Muzan Kibutsuji. I even helped you eliminate that root of evil. And now you are turning your blades on me?"
At this moment, Soma's tone had grown much colder.
"Because you are a demon."
Yuko stared at him. Her delicate face was now dark and gloomy. "Yes, you are not the root of these sins. The root of all past sins was Muzan Kibutsuji. You even did many things to end that source of evil. But none of that changes the fact that you are a demon."
"Yes. Even now, you have never committed any evil deeds or created any sins. If you were not a demon, I would still admire you beyond words."
By this point, Yuko was gritting her teeth.
"But you… are still a demon!"
"You have not done these things yet, but what about the future? What if you do them in the future? What will you become then?"
"Countless demons have been the same. Why would you be the exception? Maybe you are different now, but what about later?"
"Who can guarantee that you will not change?"
Hearing this, Soma actually let out a cold laugh.
"So you are passing judgment on me based on nothing but the future?"
"Because you believe I will commit evil deeds in the future, you do this. Because you believe I will become like those man-eating demons, you do this."
"Isn't that correct? All other demons are like that. How could you possibly be the exception in the future?"
Yuko's face had already twisted into something almost fanatical. There was no doubt that her mind had long since been warped. In truth, most Demon Slayer swordsmen carried some degree of psychological scars because of their past experiences. Yuko Nishimura was not an exception.
"Besides, this is the medicine that turns demons into humans. I am not ending your life. I am turning you completely into a human."
A strangely holy smile appeared on Yuko's twisted face. "I… am saving you. I am pulling you out of the disgusting mire of evil demons."
"Then I suppose I should thank you."
"No need to thank me."
At this moment, Yuko even looked genuinely happy, as if everything was unfolding exactly as it should.
Soma no longer felt like arguing with someone whose mind was already broken and fanatical. He simply asked one final question in a quiet voice.
"Did you ask for my opinion before deciding to turn me into a human?"
"No, right?"
"And you said that because I am a demon, I will eventually commit sins… just like the others…"
As he spoke, he looked at Yuko with a cruel glint in his eyes.
"Then I will do exactly as you wish."
"Just as you hoped, I will walk toward the root of sin. Just as you hoped, I will become the new source of evil…"
"Just like… Muzan Kibutsuji."
A savage smile spread across his face.
"All of this is because of you. Everything that happens next was created by you. The Demon Slayer Corps spent centuries finally cleansing the world of evil demons… and you have reopened that source. The world had finally become free of terrifying, man-eating demons… and you have started a new era of terror. All the sacrifices and blood the Demon Slayer Corps has shed over hundreds of years have been made meaningless by your actions. The world will become even more terrifying than when Muzan Kibutsuji was alive. After all, Muzan still feared sunlight… but I have already overcome even that final weakness."
"More happy families will be destroyed. More innocent people will be hurt."
Soma stared straight at Yuko as he spoke.
"All of this… is because of you."
The smile that had just appeared on the girl's face froze.
Disbelief filled her eyes.
Just imagining the horrifying future he described made her entire body tremble. In an instant, she was consumed by regret.
Then she noticed something.
The wound where the needle had pierced Soma's body was moving. The medicine she had just injected was slowly being expelled from the wound, drop by drop.
"I am a far more terrifying demon than Muzan Kibutsuji. What made you think the medicine that worked on him would work on me?"
He looked down at her.
"Remember — all of this is because of you. You are the one who opened the source of evil."
At this moment, Yuko's face was filled with pain, confusion, and regret. Every emotion twisted together inside her.
Just thinking about the future that would now come to pass made her heart feel like it was being torn apart.
And all of it had been created by her own hands.
But she would not have to suffer like this for much longer.
A blade suddenly sliced across the girl's neck, which was still twisted in agony. Yuko collapsed into a pool of blood, ending her life while her face was still filled with regret and pain.
It was not Soma who had killed Yuko Nishimura.
It was Kanao.
In truth, Kanao was even a little annoyed with herself right now — annoyed that her own carelessness had allowed her uncle to be hurt.
The dead girl's eyes were wide open. Even in death, she seemed unable to find peace, tormented by the terrible future she had just helped create.
She died in great pain.
Her life ended amid tears, regret, and suffering.
The pain she felt now was a hundred times worse than the pain she had endured on the day her family's happiness was destroyed.
Soma quietly watched the swordsman die in agony. His expression remained calm — almost cold-blooded.
But so what?
Who gave her the right to judge him?
Since she believed he would commit so many evil deeds in the future, then he would simply fulfill her prophecy.
If you were so certain that this was what the future held… then why are you regretting it now?
This is exactly what you believed would happen.