Late at night, in the mansion of a wealthy family in Osaka City, Muzan—transformed into the form of a human child and wearing overalls—sat in his bedroom reading a book.
Ever since he dumped all the troublesome matters of the Twelve Kizuki onto Mitsuba over two hundred years ago, Muzan had been living quite comfortably these years.
Every day when he had nothing to do, he would search through the mountains looking for traces of the Blue Spider Lily.
When tired of searching, he would extort some money and equipment from Douma to conduct research, attempting to develop medicine that could help demons overcome sunlight.
When truly tired of researching, he could also temporarily put everything aside, change identities, become someone's husband or son, and experience a leisurely "retirement life" to relax and unwind…
Simply too comfortable.
As for the Twelve Kizuki, demon hunters, the Ubuyashiki family, Upper and Lower Rank meetings—all these messy annoyances had not appeared in Muzan's life for over two hundred years.
No ants jumping out to bother him, no need to worry about useless fools, doing whatever he wanted every day, and not even needing to earn money himself when short on funds.
Honestly, in Muzan's view, these past two hundred-plus years were absolutely the most comfortable period in his thousand-year demon life.
At the same time, Muzan had therefore not personally seen Mitsuba for roughly two hundred-plus years.
Mitsuba's personality was such that she would never actively come to find him unless there was something important.
Such as tonight.
In the study late at night, the bedroom window wide open, Mitsuba's figure wrapped in silver moonlight gently descended from outside the window, her robes fluttering.
"Good evening, Lord Muzan."
After such a long interval, personally coming to pay respects to Muzan again, Mitsuba had specifically changed into a kimono this time to show solemnity.
However, as the demon in the Twelve Kizuki who hated being bound by rules the most, although she wore a kimono, she wore it very casually.
Not only was the hem not closed, the waist was not tied either—she simply draped it over her body like a robe, her posture quite relaxed.
Solemn, but not completely solemn.
Of course, Muzan didn't care about these things either.
"Long time no see, little Mitsuba."
Turning a page of the book in his hand, regarding Mitsuba who suddenly appeared in the room, Muzan asked with a low voice completely mismatched to his figure:
"Aren't you supposed to be being your editor in your Tokyo? How do you have time to come see me?
Don't tell me you came because of that Lower Rank demon killed by demon hunters last night."
As the Demon King who could sense all demons in this world, Muzan naturally knew that another Lower Rank demon had been slain by demon hunters last night.
Although he knew, Muzan didn't care about such matters.
After all, Lower Rank demons had always been like this—he had long grown accustomed to it.
As long as there were no problems with the Upper Rank demons, maintaining suppression of the Demon Slayer Corps and preventing those demon hunters from bothering him was sufficient.
In this regard, Mitsuba had done very well for the past two hundred-plus years.
"Of course not. How could I disturb Lord Muzan with such trivial matters."
Walking directly to an empty seat specially prepared nearby and sitting down, Mitsuba smiled and replied:
"I came here this time actually to apply for something from Lord Muzan."
"If it's about the Twelve Kizuki, I've already said—you may handle it as you see fit, little Mitsuba. No need to come ask me again."
"I understand. It's just that what I plan to do this time is slightly special. I believe I must explain clearly to Lord Muzan in advance…"
Saying thus, Mitsuba's expression finally became serious.
"Lord Muzan, I intend to completely dissolve the Lower Rank demons.
Not elimination, but from now on, no longer establishing Lower Rank demons among the Twelve Kizuki."
"Oh?"
Hearing this, Muzan's attitude also finally became serious. He closed the book in his hand, turned to look at Mitsuba, and asked curiously:
"Mitsuba, what is your reason for doing this?"
"Because Lower Rank demons no longer have any necessity to continue existing."
Mitsuba replied quite directly.
"Lord Muzan, I have made preparations to completely eradicate the existence of demon hunters from this world within at most one year.
By that time, the Twelve Kizuki—which originally existed to deal with demon hunters—will no longer need to maintain their existence either.
And the Lower Rank demons, these creatures that are useless to keep yet regrettable to discard, can perfectly serve in advance as bait to stimulate those demon hunters' confidence and make them actively jump out to their deaths."
"Eradicate demon hunters?"
Hearing Mitsuba's explanation, Muzan suddenly laughed out loud.
"Little Mitsuba, if I recall correctly, you used to always proclaim yourself some kind of 'dove faction.'
Constantly muttering those mystical things in my ear, telling me to coexist with demon hunters? Why do you suddenly want to eradicate them?"
"Lord Muzan, times change, and our decisions must always change according to the situation's evolution.
As of now, I am very certain that eradicating the existence of demon hunters and the Ubuyashiki family is absolutely better than continuing to keep them."
"Then how do you specifically plan to do it?"
Muzan asked curiously.
Mitsuba continued explaining:
"In the near future, I will gather those Lower Rank demons and arrange for them to engage in a direct confrontation with demon hunters.
Of course, with their strength, once they encounter the Hashira of the Demon Slayer Corps, they will inevitably collapse.
Therefore, this is actually a 'great victory' we are gifting to the Demon Slayer Corps.
After all, these demon hunters have not successfully defeated an Upper Rank demon for over two hundred years.
Currently, they have no understanding of Upper Rank demons' true strength.
So, we need to use this 'great victory' to mislead their judgment of Upper Rank demons' strength and stimulate their confidence.
Thus making them develop a contemptuous mentality of 'if Lower Rank demons can be so easily slain, then Upper Rank demons must be nothing special either.'
Finally step by step luring them, driven by this thinking, to jump one after another into that abyss we have long prepared for them…"
"Hmm… sounds like a very interesting plan. Just one thing I'm curious about."
Quietly listening to Mitsuba's account, Muzan continued asking:
"With Mitsuba's Blood Demon Art abilities, even without these complicated plans, you should have confidence in eradicating demon hunters and that Ubuyashiki family, right?"
The power of karma had absolute restraint over humans.
Muzan was very clear how terrifying a deterrent Mitsuba's existence was to those demon hunters.
One could even say that Mitsuba alone created more pressure on the Demon Slayer Corps than all other demons of the Twelve Kizuki combined!
She completely had the ability to single-handedly crush the entire Demon Slayer Corps!
"That is not safe, Lord Muzan."
To this, Mitsuba instead slightly shook her head:
"The Ubuyashiki family ultimately has divine protection. If we take the initiative to attack, there is high probability that bloodline members of this family will escape as fish that slip through the net.
So, rather than taking the initiative to attack, replicating our experiences of the past several hundred years once more.
I personally believe it would be safer to wait for them to come to us, letting us catch their weaknesses…
Of course, all of the above are additional reasons.
To be honest with you, Lord Muzan, the true reason I want to meticulously plan all this and slowly guide those demon hunters has from beginning to end been only one…"
Her blood-red pupils full of cold intent, yet a brilliant smile blooming on her face, Mitsuba looked at Muzan before her and said with a smile:
"As the final battle between us and demon hunters over this millennium, I do not wish for it to end too hastily.
The finale of a stage play should always appear more magnificent and passionate, otherwise it would truly be somewhat too boring, wouldn't it?"
"Hahahaha!"
Seeing Mitsuba finally speak the truth, Muzan immediately threw his head back and laughed heartily.
He raised his finger pointing at Mitsuba, unable to resist laughing and cursing:
"I knew it! All those messy reasons just now were completely false!
Little Mitsuba, you—only making yourself happy has always been the real truth!
Forget it, do as you please from now on, no need to come ask me again.
I don't care about the process; I only want Mitsuba to bring me the final result."
"Of course, Lord Muzan."
…
(Considering certain unspeakable mysterious reasons, the Mount Natagumo arc has been skipped meow~)
(Next, the Mugen Train arc is about to begin meow~)