Yoriichi left, his departing figure somewhat lost and dejected.
He didn't say words like "I will stay to accompany you until the end," nor did he do so. Instead, he painfully and silently accepted all of Mitsuba's arrangements and returned to the Demon Slayer Corps alone.
This was the natural outcome—Mitsuba had long foreseen this.
After all, Brother Yoriichi was the "Child of God."
The deities had long arranged his path for him, and this did not change according to his will.
Yoriichi still had his own mission to complete, and before this mission was achieved, no matter how Yoriichi deviated, the deities would ultimately pull him back onto this path.
Therefore, Mitsuba knew from the very beginning that Yoriichi could not stay.
Even if he wanted to, fate would arrange for him to leave.
Everything was long predetermined.
"Whoosh—Boom!"
In the darkness of night, sitting at a table illuminated by candlelight, Mitsuba—who was carefully drawing the sword techniques of the breathing styles she remembered in her mind into a book—suddenly heard bursts of explosions coming from the window behind her.
She turned to look and saw under the night sky, dots of light continuously rising from the city, bursting into brilliant fireworks, echoing the lively scene of lanterns everywhere below in the city.
"What day is it today?"
Feeling puzzled by this, Mitsuba asked.
Outside the door, a waiting maid immediately replied upon hearing her voice:
"Reporting to the family head, today is the day the fireworks festival begins. You specifically instructed a few days ago that this year's fireworks festival should be organized by the common people of the city themselves..."
"Is that so..."
Vaguely recalling that there indeed seemed to be such a matter, Mitsuba closed her eyes and raised her hand to her forehead.
Her memory seemed to be getting worse lately, occasionally forgetting things from time to time.
Well, considering that her brain was now almost as half-dead as herself, and it was only occasionally forgetting some unimportant matters, it was really trying very hard...
Forget it, self-mockery can wait until after death. Right now, she should seize the time while she still remembered to quickly record those breathing techniques Brother Yoriichi demonstrated earlier and send them to Butterfly...
Thinking this, Mitsuba was about to pick up her brush to continue drawing when she suddenly seemed to remember something. She turned toward the door and instructed:
"Since tonight is the fireworks festival, then all of you go out to play too. Don't wait outside the door."
"Family head, we must stay to take care of you."
"Enough, I'm right here in the room. There's no need for care. Quickly, go."
"This..."
Persuaded repeatedly by Mitsuba, the maids outside gradually began to hesitate.
After all, her maids were almost all in their teens, and children of this age—there were none who didn't love to play.
"Yes... then family head, we will return later. You should rest early too, alone."
"Mm."
In the end, nature triumphed over reason. After leaving these words, the footsteps of the maids quickly faded away in the corridor outside.
It could be heard that they had indeed wanted to go out and play for a long time.
With a trace of a smile at the corner of her mouth, Mitsuba refocused her attention on the book before her.
On the book were page after page of "sword-dancing figures" carefully outlined by her with a brush.
On each page, Mitsuba not only seriously recorded the breathing secrets Yoriichi had told her.
She also considerately used small characters to add detailed annotations about details such as how high to raise the arms when executing these techniques, how to step with the feet, and how to coordinate the waist, and so on.
So meticulous—Mitsuba believed that as long as one could read, even someone who knew nothing at all about martial arts could learn seven or eight parts from this illustrated manual based on the explanations above, enough for Butterfly to use for research.
These past few days, in order to complete this manual as soon as possible, Mitsuba hadn't even gone to Butterfly's clinic for treatment.
Because her time was truly running out.
Even without Yoriichi's Transparent World, Mitsuba could clearly feel this.
Every morning when she woke up, she could clearly feel that her brain had died a bit more.
Memories of the past remained clear, but recent memories became increasingly blurred and chaotic.
Books she had clearly finished reading—when she turned back, she completely couldn't remember their contents.
Matters she had clearly instructed in advance—upon waking, she would completely forget.
Even things she had done just a second ago, she would completely forget the next second.
At the most severe times, Mitsuba would even sit dumbly at her desk before the book, staring blankly at the manual on the table.
But different from "spacing out" in the general sense, she clearly knew what she should be doing now. She knew she should immediately grind ink, then pick up the brush, and continue writing and drawing...
But for some reason, even such a simple sequence of commands, her brain seemed unable to comprehend, completely unable to issue any instructions.
So much so that Mitsuba could only sit dumbly at her desk like this, until the maids outside discovered her abnormality.
And similar situations were becoming increasingly frequent.
So, her time was truly running out...
If she didn't seize the time while she still remembered, while she could still maintain normal thinking ability for a certain period each day, to quickly record those breathing techniques.
Perhaps one day when she woke up, she would truly forget everything completely...
She only hoped that when she saw Butterfly again later, she wouldn't blame her.
Under the dim candlelight, the room was so quiet that only the rustling sound of the moist brush tip gently gliding across the paper could be heard.
Time slowly passed amidst this, and the sound of fireworks outside the window gradually subsided, announcing the end of tonight's first round of fireworks.
"Click!"
Suddenly, a crisp sound came from the window behind her, as if something had hooked onto the window frame?
Although she heard this movement, her sluggish brain couldn't immediately react to this abnormality. Mitsuba only focused intently, continuing to concentrate on the book before her.
Until, that familiar cheerful voice rang out.
"Wow~ Mitsuba, your room is really high! It took me so much effort to climb up here..."
This was Butterfly's voice.
Butterfly?
Strange, why was her voice appearing here?
Her brain finally detected a trace of abnormality. Mitsuba turned back in confusion, and then saw the most unbelievable scene.
Under the moonlight, Butterfly's figure was just climbing in through the window. She carried a large basket on her back, supporting herself against the wall with one hand on her hip, panting nonstop.
"Butterfly?"
Her brain couldn't comprehend the situation before her for a moment. Mitsuba stared blankly at this figure that she didn't know why was appearing in her room, subconsciously standing up.
"You—why are you here?"
"Why else? Of course I came to find you, Mitsuba!"
Finally catching her breath, Butterfly raised her hand to her chest and said with a resigned tone:
"These past few days you neither came to the clinic, nor sent anyone to tell me what the situation is... do you know how worried I was about you?"
"No, I'm asking you—how did you get in?"
Mitsuba pressed.
The room she was in was almost at the highest point of this castle tower, at least a dozen or so meters from the ground. How did she sneak in?