Because of the sins she had committed in the past, Tamayo had never clung strongly to life.
The only reason that had kept her alive was the desire to kill Muzan Kibutsuji.
Only when she thought of killing Muzan could Tamayo faintly feel that her heart was still beating.
For Tamayo, today was not only the day Muzan Kibutsuji would be ended.
It was also meant to be the day she ended her own life.
Because once Muzan Kibutsuji was dead, the hatred that had sustained her for hundreds of years would vanish completely. Her life would no longer have a goal.
But Soma's words made a new belief rise within Tamayo's heart.
As a mother who had once suffered from a grave illness and only wished to see her child grow up healthy, Tamayo understood deeply the pain of those tormented by sickness. They were not truly afraid of death. They simply had too many things they could not bear to leave behind.
Her past self had been unable to let go of those things, and because of that, she had fallen for Muzan Kibutsuji's deception, committing acts she could never forgive herself for.
Now, she possessed excellent medical skill. Perhaps, for the rest of her life, she could save more people like her former self, people trapped in desperate situations.
If she could help those people, help those who suffered from terminal illness as she once had, then that would be far more meaningful than death.
That would be the best redemption for the wrongs she had committed in the past.
All at once, Tamayo's nearly dead heart seemed to slowly regain life.
She had found a purpose for her life again.
"Thank you, Mr. Soma."
Tamayo bent at the waist, placing her small hands over her abdomen as she bowed respectfully to Soma.
Soma nodded. His gaze moved away from Tamayo and fell upon Muzan Kibutsuji.
At this moment, the progenitor demon, after being injected with Tamayo's medicine that could turn demons back into humans, was aging at an extremely rapid pace. His once vibrant skin was continuously withering away.
Soma could feel that Muzan's strength was weakening at an alarming rate.
However, as the first demon, the cells in Muzan Kibutsuji's body were extraordinarily active, and he possessed an extremely powerful ability to break substances down. Although this medicine that could turn demons back into humans was something Muzan had never encountered before, still—
as long as he was given time, Muzan Kibutsuji would certainly be able to break down the medicine.
But all of that required time.
And clearly, Soma would not give Muzan Kibutsuji time.
Holding his Nichirin Sword, he walked step by step toward Muzan Kibutsuji.
Sun Breathing flowed with each breath, spilling from Soma's nose and mouth as scorching mist.
"Nakime…"
Muzan Kibutsuji almost growled the name.
"Infinity Castle."
A soft murmur suddenly rang out.
In the next second, space itself seemed to overturn. Across the entire Yoshiwara Entertainment District, whether demons or swordsmen, everyone who was still fighting suddenly felt the ground vanish beneath their feet.
Then their bodies began falling into an enormous underground city.
This was the Blood Demon Art controlled by Upper Rank Four of the Twelve Kizuki, Nakime.
"Infinity Castle" was a Blood Demon Art that created a separate dimension. The entire space of the Infinity Castle centered around Nakime, complex and labyrinthine. By playing the biwa in her hands, Nakime could control the entire castle, pull any target into it, and transfer them anywhere within its interior.
Nakime could manipulate the terrain of the Infinity Castle to exhaust her enemies and make it difficult for them to approach her.
Of course, she could also use it to hide people away.
Or to delay time.
Although this Blood Demon Art did not possess much killing power, it was first-rate in how troublesome and difficult it was to handle. As long as Muzan Kibutsuji was dragged into the Infinity Castle, it would buy him enough time to break down the medicine inside his body.
Even if the sun rose, as long as the Infinity Castle existed, sunlight would not be able to reach him inside.
Of course, ordinary Blood Demon Arts could not exist beneath sunlight. But Infinity Castle was an exception. It was not that this Blood Demon Art could appear under the sun, but rather that once Infinity Castle was activated, it would sink into a place beneath the earth where sunlight could not reach.
In the original future, Nakime's Infinity Castle caused the Demon Slayer Corps no small amount of trouble, and it also bought Muzan Kibutsuji enough time to break down the medicine inside him.
If things followed that original course, everyone would probably waste a great deal of time and strength inside the Infinity Castle.
...
The ground vanished beneath his feet, and Soma fell in.
His entire body dropped into an enormous underground city.
Looking at this vast subterranean city, packed with countless structures, Soma could not help sighing at how impressive Nakime's spatial Blood Demon Art was. No wonder Nakime, who had almost no offensive ability, had earned Muzan Kibutsuji's trust and become Upper Rank Four.
If it had been before, Soma would probably have had no choice but to search slowly within the Infinity Castle for Nakime's location or Muzan's.
But after killing the former Lower Rank Six of the Twelve Kizuki, the Drum Demon Kyogai, he had obtained a spatial Blood Demon Art of his own.
Looking at the underground city before him, Soma slightly closed his eyes and spoke softly:
"Blood Demon Art: Drum House."
A house suddenly appeared out of thin air.
If Kyogai were still alive, even using Blood Demon Art: Drum House would not have allowed him to oppose the Infinity Castle. After all, it was because of his lack of talent that Kyogai had been stripped of his position among the Twelve Kizuki.
But right now, the one using Drum House was Soma.
And the Drum House he used was far stronger than Kyogai's.
The moment Drum House appeared, it began expanding rapidly. Almost immediately, it started devouring the surrounding area and spreading farther out. Infinity Castle seemed to resist with all its strength, and the two spatial powers clashed constantly.
During that clash, Soma quickly located Nakime, who was controlling Infinity Castle and resisting his Drum House.
He stepped forward.
In almost no time, Soma arrived in a room and saw a young woman holding a plectrum in one hand and a biwa in the other.
Her skin was grayish-white, and she had long black hair with bangs falling on both sides, her hair just covering her face.
At this moment, with Soma's arrival, the young woman lifted her head in shock. Her gaze toward him was filled with terror.
"Nakime."
Soma looked at the girl and spoke in a low voice.
Nakime's expression changed drastically. Almost without thinking, she turned to flee.
Behind her, a sharp blade light flashed and fell across her head as she turned.
Crack!
The sound of breaking bone rang out, followed by Nakime's head flying through the air.
As an Upper Rank demon, Nakime had been beheaded with almost no resistance at all. She hadn't been able to display any of the strength expected of an Upper Rank demon.
Soma was not surprised by this.
Among the Upper Ranks, Nakime had been valued by Muzan solely because of her "Infinity Castle" Blood Demon Art. Aside from that, her own combat strength was actually quite ordinary.