Demon Slayer: The Journey That Began When I Became Yoriichi's Sister

Tamayo nodded and said, "You should know that cells will slow down their division rate under extremely cold or hot external conditions."

"Even the blood of demons is no exception."

“In other words…” Tamayo raised her head slightly, a glint of light appearing in her purple eyes, “Ikuko, your blood already has the effect of replacing the Crimson Blade.”

“A replacement for the Crimson Blade…” Yuko’s expression was somewhat moved.

Now her Blood Demon Art's only weakness against demons is gone.

Furthermore, it can be configured for swordsmen who have difficulty activating the Crimson Blade, enhancing their offensive capabilities.

The Crimson Blade is a technique that uses wrist strength to activate the solar energy within the Nichirin Blade, requiring unimaginable wrist strength.

After she successfully awakened her mark, she naturally mastered the Transparent Domain due to her improved swordsmanship, but she failed to master the Crimson Blade.

It was only during her battle with Kokushibo, when she was on the verge of death, that she unleashed that power for a fleeting moment.

After becoming a demon, her physical abilities improved, which allowed her to fully master the Crimson Blade.

In Yuko's opinion, even if all the swordsmen of the current Demon Slayer Corps had activated their Demon Slayer Marks, only two of them could actually activate their Crimson Blades.

That is, the Stone Pillar with the strongest arm strength, and the Sound Pillar whose arm strength is second only to his—Uzui Tengen.

Moreover, after Uzui Tengen activated his mark, Ikuko had already made him try it. Unfortunately, even with the second-best arm strength among the Pillars, Uzui Tengen couldn't successfully activate his Crimson Blade, even though his face turned red from straining.

Even after Yuzui Tengen spent a long time trying to figure it out without success, he began to doubt the truthfulness of Yuko's words. Of course... Yuko demonstrated for him with his twin swords what it meant to hand over a yellow sword and return it with a red one.

However, the fact that even Yuzui Tianyuan couldn't easily activate the Crimson Blade proves how difficult it is to activate, not to mention something as mysterious as the Transparent Domain.

Yuko's idea was that the three-piece set could be configured to create the team's markings before the final battle, but she didn't plan to force the Transparent Domain and the Crimson Blade.

In dire circumstances, what can be controlled will naturally be controlled.

From the moment Yuko learned of the effects of Blood Demon Art, she had considered using it on her Nichirin Blade to help others gain an advantage in battle.

However, after her later attempts, she discovered that the cold air from her blood affecting the blade prevented it from heating up properly.

Because of this, she gave up the idea of ​​applying the Blood Demon Art to other people.

After all, increasing the range of sword energy is not as effective as using the Crimson Blade in killing Upper Moons and Muzan.

But now that Tamayo has said that, she feels that her Blood Demon Art is working again.

Looks like I'll have to find some ghosts to test the knife on and see how it goes.

Tamayo said softly, "If I'm not mistaken, your blood temperature should continue to drop."

"Why did it suddenly mutate now?" This was the point that Yuko didn't understand.

Nothing has changed in the hundreds of years except for this point in time.

“Hmm, I’m not too sure about that either.” Tamayo pressed her pale fingers to her lips. “But I guess it might be related to your long-term fasting.”

"After such a long period without food, even a ghost's cells would be extremely deteriorated. Suddenly eating could cause some changes in the body."

"But then again, when you're feeling unwell, any normal person would try to help themselves or see a doctor, right?"

Yu Zi opened her mouth, then retorted, "How am I supposed to find a doctor?"

Tamayo lowered her eyes: "You know that's not what I meant."

"It's amazing you could put up with this..."

At this point, Tamayoshi couldn't help but frown slightly.

Even for a ghost, going two hundred years without eating is an unimaginable concept.

Just because you won't die doesn't mean you'll be safe.

Ghosts are more likely to lose their minds when they are hungry.

This is why most people lose their minds during the initial period after being transformed into ghosts.

Because becoming a ghost requires consuming energy within the body, the more powerful a person is, the longer it takes to become a ghost, and the greater the energy consumption.

Being able to remain rational under such circumstances cannot be simply attributed to strong willpower; it is absolutely inseparable from the special nature of one's physical constitution.

Otherwise, they wouldn't have had to modify their bodies by drinking blood to adapt.

Just endure it.

But even the simplest act of enduring hunger is not something just anyone can endure for two hundred years.

Ikuko: "..."

Ok.

do not talk.

She already knows she was wrong.

Tamayo concluded, "In short, although we don't know the specific reasons, it should be evolving in a positive direction."

"You should pay close attention to your body during this time. If you feel unwell, tell me immediately, or you can tell Miss Shinobu as well."

Ikuko: "Ouch."

I always feel like my best friend doesn't really trust me.

"Wait a minute." After receiving Yuko's affirmative answer, Tamayo casually said this and turned around to rummage through the table.

"What are you looking for?" Yu Zi casually glanced around the laboratory.

"The purpose of calling you here today." Tamayo fiddled with something on the table without turning her head.

Yuko asked doubtfully, "The purpose? Isn't it my blood?"

"..." Tamayo turned around with a syringe in her hand, and said helplessly, "I was only speculating about the changes in the blood at first. Didn't you only realize the problem after you came over?"

"Ow."

What happened to this child?

Why are you a little slow-witted after not seeing each other for two hundred years?

Tamayo's gentle voice carried a hint of helplessness: "Stretch out your hand."

"Hand?" Yuko shuddered, averting her gaze from the lab and looking at the needle in Tamayo's hand. "Weren't we not going to draw blood?"

Tamayo: "It's an injection."

Yuko was taken aback: "Inject what?"

Tamayo smiled slightly, keeping everyone in suspense, and said, "It's something interesting that should surprise you."

"Alright, give me your hand." Tamayo beckoned.

Although it's a bit of a mystery, the two have shared joys and sorrows for hundreds of years, and Ikuko has complete confidence in Tamayo.

Let alone injecting some unknown liquid, she wouldn't even flinch if Yu Zi were to bang her head against a wall.

With her arm resting on the table, Tamayo pushed the syringe through her skin.

"Alright, wait a little longer for the medicine to take effect." Tamayo put away the empty syringe and rolled up Ikuko's sleeve.

"Ah."

To keep her from getting bored, Tamayo rummaged through the freezer for blood bags: "Hey, you can drink from these blood bags first."

"Hmm..." Something seems off.

I always feel like I'm a kid who's just mooching off my neighbor.

but……

It's not bad to have food.