How long can a person sustain their hatred?
To this question, Tamayo's answer was—forever.
Essentially speaking, wanting to maintain hatred toward someone for a long time, especially when that person is someone you normally cannot reach, is actually a very difficult thing.
No one knew how Tamayo managed to silently sustain her hatred toward Muzan for hundreds of years.
But she indeed accomplished it.
For hundreds of years, no matter how the times changed, how society developed, how humanity progressed, only her hatred toward Muzan remained constant, never changing.
This was truly an unbelievable miracle.
Hundreds of years ago, after the subjugation operation she assisted the Demon Slayer Corps in launching against Tsugikuni Mitsuba failed, Tamayo once again began her wandering life of hiding everywhere.
That failure taught Tamayo a profound lesson—
Tsugikuni Mitsuba cannot be defeated.
Her existence was an insurmountable chasm that Demon Slayers could never cross.
Even if they calculated against her to the extreme, as long as she had even a trace of strength remaining, she could instantly reverse the situation with that tiny bit of power.
Not to mention, since Tsugikuni Yoriichi's passing, there no longer existed any Demon Slayer in this world capable of forcing Tsugikuni Mitsuba into such a desperate situation.
She was a bug in this world, an existence that could not be defeated by Demon Slayers, yet she indeed stood before Muzan, blocking the path of all Demon Slayers toward slaying the progenitor demon.
This situation was so despair-inducing that for hundreds of years, Tamayo could think of no way to break this deadlock.
All methods she could think of, all things she could do, would be easily countered by Tsugikuni Mitsuba.
One could say that the possibility of convincing Tsugikuni Mitsuba to commit suicide was much higher than the possibility of letting Demon Slayers kill her.
And what made Tamayo feel even more desperate was that Muzan didn't have only Tsugikuni Mitsuba as a demon under her command.
The existence of the Twelve Kizuki was equally despair-inducing.
Although she had been hiding for hundreds of years, occasionally in the past, Tamayo would still encounter some Demon Slayers.
Like a few years ago, she had accidentally learned from a Demon Slayer swordsman who happened to enter her clinic without knowing her identity that the current Demon Slayer Corps had not defeated an Upper Rank demon for nearly two hundred years.
This was truly a desperate and helpless situation.
Today's Demon Slayers, let alone defeating Tsugikuni Mitsuba, couldn't even defeat the other Upper Rank demons.
Did this so-called thousand-year war between demons and Demon Slayers really have any meaning in continuing?
"Ah, right, Miss Tamayo."
Just as Tamayo was deeply contemplating these questions, in a daze, that familiar, smiling voice once again sounded beside her.
She subconsciously turned to look, only to see Mitsuba, dressed in a loose kimono, sitting on the sofa beside her at some unknown time, swinging her legs, looking at her with a face full of smiles.
"Although you may not consider me a friend, I have always thought you were a very good person..."
[Tsugikuni... Mitsuba?]
Staring blankly at this suddenly appeared figure, Tamayo's pupils contracted sharply.
"So, consider this as me speaking out of turn with some unsolicited advice."
Completely unresponsive to Tamayo's shock, Mitsuba simply tilted her head, looking at her with a smile, and softly advised:
"It would be better for you to put down the past as soon as possible and move toward your new life, no?
Don't end up becoming like my elder brother in the end..."
"Y-you, why are you appearing here, what exactly are you..."
Bone-chilling cold rose from the soles of her feet straight to the crown of her head, extreme fear rapidly spreading through her heart.
Staring incredulously at Mitsuba on the sofa, Tamayo subconsciously took two steps back.
*Crash!*
"Doctor Tamayo? Are you alright?!"
Her body bumped into the shelf behind her, making a loud noise.
On the hospital bed before her, the man who had been lying there waiting for Tamayo to bandage his arm wound hurriedly asked.
"I..."
As if suddenly coming back to her senses, Tamayo's gaze fell on the concerned man before her. She blinked in confusion, then suddenly turned her head again to look at the sofa beside her.
There, Mitsuba's figure was long gone.
No—there had never been anyone there from the start.
[Another hallucination, this time trying to persuade me to turn back...]
Completely coming back to her senses, realizing this, Tamayo raised her hand to gently wipe the sweat from her forehead.
Yes, everything that happened just now was an illusion.
Her hiding place had not been exposed, Tsugikuni Mitsuba had not appeared before her—everything was a fantasy of her mind.
Similar hallucinations had occurred countless times over the past hundreds of years.
When exactly the first hallucination started, Tamayo could no longer remember.
By the time she came back to her senses, she was already being repeatedly tormented by these hallucinations.
Every time she became distracted, every time her spirit weakened, the phantom named Tsugikuni Mitsuba would suddenly appear beside her, repeatedly reciting different words to her.
Of course Tamayo remembered the origin of those words just now—they were the advice Mitsuba gave her during their last parting hundreds of years ago.
Tsugikuni Mitsuba said she considered her a friend and hoped she could put down the past and start anew.
[Put down the past, huh...]
Subconsciously, Tamayo slightly lowered her head, her eyelids drooping.
What appeared in her mind at this moment was the incomparably bloody and sticky sensation when she had personally devoured her husband and children with her own hands.
This was a painful memory that she could not forget even after spending hundreds of years.
[Mitsuba, if the past were truly that easy to put down, then how could there still be so many suffering people in this world...]
Sometimes, Tamayo would even have a strange feeling.
She always felt that she and Tsugikuni Mitsuba were like two people walking toward different extremes.
Clearly they both had equally painful pasts, had people they could equally resent, yet Tsugikuni Mitsuba did not maintain the hatred in her heart like she did.
On the contrary, after transforming into a demon, she quickly put down her past, put down her resentment toward her original family, toward her two elder brothers...
From Tsugikuni Mitsuba's perspective, she had reasons to sustain her hatred forever, even to find ways to retaliate against and torment them.
So Tamayo could not understand—faced with the pain she experienced as a human, how could she abandon it so easily?
"Because, I want a new life, Miss Tamayo."
Behind her, Mitsuba's voice sounded once again.
"For living beings, rather than indulging in the past that can no longer be changed, moving toward a new future as soon as possible—this is the most suitable choice."
This time, she suddenly appeared behind Tamayo, whispering softly with a smile beside her ear:
"I don't want to let hatred consume my heart. I want to begin that truly new life that belongs to me, so I chose to reconcile with the past.
Miss Tamayo, you have always known this answer, haven't you?"
Hearing this, Tamayo lowered her head and remained silent.