Chapter 25 — Planting a Demon Seed
Outside.
While Aizen and Ido confronted one another within the depths of Yakumo's soul—
Kurama Yakumo's small body, lying upon the operating table, suddenly convulsed violently, as if seized by a terrible seizure.
Her arms and legs jerked uncontrollably, and in her terror, she clutched the steel guardrails of the table with such force that the thumb-thick metal bars twisted in her grip.
A strangled, muffled whimper escaped her throat as she struggled.
If not for Aizen's palm resting gently yet firmly upon her forehead, anchoring her soul within the seal, she would have already broken free.
"Murakumo—Yakumo, she…"
Kurama Rin could no longer hide the panic in her voice as she looked toward her husband.
But the clan head, Kurama Murakumo, wore a deep, complicated expression—
one mixed with fear, hope… and anticipation.
"Don't worry," he murmured.
"Aizen-kun must have reached the core of the problem."
"Perhaps… this time…"
Even Yūhi Kurenai, standing beside them, glanced at Aizen with a newfound sense of awe.
Aizen had always been popular among their peers, but his actual combat talent was nothing special in childhood.
No one expected him to advance so far into the study of Yin Release—
far enough to attempt a soul-level treatment.
Not bad at all, Sōsuke…
Just then—
Aizen opened his eyes.
His palm lifted slowly from Yakumo's forehead.
From between his raised fingers, threads of tangible, heavily condensed black chakra were pulled free—
dragged out from the very depths of Yakumo's soul.
The moment that malignant chakra left her—
Yakumo's contorted expression relaxed, her breathing steadied, and the pain vanished from her face like fog burning away under sunlight.
"Aizen-kun!"
Kurama Rin could no longer restrain herself, stepping forward with desperate hope.
Aizen blinked as though returning from a trance, then offered the couple a gentle, warm smile.
"I have not failed you."
At that sentence—
The Kurama couple and Kurenai all exhaled at once.
Relief washed over them, mixed with disbelief.
The curse that plagued their clan for generations…
solved just like that?
But Aizen calmly continued:
"However, I've only isolated the source of the corruption within Yakumo-san's soul."
"To restore her body to a state where she can safely become a shinobi…
will take time. A long time."
"And as for her talent…"
His tone trailed off.
Husband and wife exchanged a look—disappointment flickered in their eyes, but neither seemed surprised.
Kurama Rin offered a soft sigh.
"As long as she can live… that is all we ask."
The Kurama clan knew their history well.
Those blessed—and cursed—with Yakumo's level of talent rarely survived past twenty.
Their immense Yin chakra hollowed out their life force; even a fever could become a death sentence.
Murakumo suddenly seemed to remember something, leaning forward urgently.
"Aizen-kun… may I ask—what exactly causes our clan's 'bloodline illness'?"
This was a matter that could reshape the future of the Kurama clan.
If this condition could be identified and controlled, then those gifted but doomed children might finally survive long enough to carry on the clan's legacy.
Aizen had long prepared for this.
Ido still had its uses.
And he intended to continue experimenting on Yakumo.
Revealing the true nature of the Kurama bloodline would only ruin that opportunity.
So instead, he lifted his hand—
Between his fingers, the tightly bound black chakra writhed like a living thing.
"Strictly speaking," he said gently,
"this is not an illness at all."
"It is an overpowered ability… turning inward."
"The Kurama bloodline distorts the five senses through imagination, imposing illusions so vivid that they can overwrite reality itself."
"But before this power affects an enemy—"
"It affects the user."
"Yakumo-san was being corroded by her own ability."
He lifted the thrashing black chakra slightly.
"This is a fragment of Yakumo-san's soul… warped by her bloodline power."
The Kurama couple stared blankly, barely understanding, yet completely believing.
Aizen's voice was truth—
divine truth, in their eyes.
Murakumo even looked ready to start taking notes on the spot.
But then a new fear struck him:
"Then… how do we treat it?"
Aizen sighed softly, expression tinged with regret.
"Since the corruption originates from Yakumo herself…
the only cure is to cut away part of her soul."
"That is why I said… her innate talent may not remain."
"That…"
Murakumo froze.
Rin clutched her husband's sleeve, whispering:
"Murakumo… if it will keep her alive, then let Aizen decide."
"If we ignore it… we may lose her before she reaches twenty."
The history of their clan's prodigies made the point painfully clear.
Murakumo exhaled heavily.
What was talent, compared to a child's life?
They were already elite jōnin.
Their daughter did not need to become a hero.
In times of peace, a normal shinobi life was safer—
perhaps even happier.
He opened his mouth to agree—
Until a weak yet stubborn voice trembled from behind them.
"NO! I don't want that!"
Yakumo struggled upright on the table, gripping its edge as she glared at her parents.
"Father!"
"I want to become a strong shinobi!"
"If I lose my bloodline power… then…"
She knew her own body better than anyone.
Without her bloodline, she might never even make chūnin.
Becoming a great kunoichi—becoming like Lady Tsunade—
had been her dream since childhood.
A dream shaped by her parents' own hopes.
"Yakumo…"
Murakumo's expression twisted with pride and heartbreak.
Even Aizen glanced toward her, interest flickering behind his calm eyes.
Kurama Yakumo lifted her head—
This time, there was no trace of the timidity or hesitation she showed earlier.
Her small face was tense, yet determined, as she looked directly at him.
After a brief moment of silence, she spoke—firm, pleading:
"Aizen-sama… please… let me keep my bloodline ability!"
The Kurama couple and Yūhi Kurenai all turned toward him.
Aizen, meanwhile, wore a thoughtful, almost pensive expression.
"So… suppressing Ido temporarily has allowed her true nature to surface?"
Behind the reflection of his glasses, his eyes glimmered with faint interest.
In truth, Aizen had no intention of simply destroying the entity known as Ido in one go.
If he wished, he could crush the creature with raw spiritual pressure in an instant.
But Ido, as a manifested cluster of negative chakra, possessed one extraordinary trait—
limitless accumulation.
Ido was a "demon seed" planted deep within Kurama Yakumo's soul.
As long as Yakumo remained intact, Aizen could cultivate her—
harvest her—
again and again, like a field rich with spiritual crops.
Each harvest of condensed negative energy, even if small, would feed perfectly into the forging of a Zanpakutō.
Thus—
He needed Yakumo's cooperation.
He needed Yakumo herself.
Talent like hers—
a soul twisted yet overflowing with potential—
was indispensable.
Aizen remained silent, as if weighing matters carefully.
Yakumo stared at him, eyes filled with hope and desperation.
It was a long time before he finally spoke:
---
"Yakumo-san."
"If you wish to keep your gift and still become a shinobi… there is a way."
"However… it will inflict severe strain upon both your mind and your body."
"It may cost you your life before the age of forty."
"And from now on, you will endure constant pain—
cutting apart fragments of your own soul,
suppressing your bloodline power to the limits of your endurance,
again and again—
until the day your life ends."
Aizen paused, letting the weight of his words settle.
"Even so… are you willing?"
At those words—not only Yakumo, but even her parents straightened, eyes shining.
Forty years—
for a shinobi, that was more than enough.
And for Yakumo… it was a chance at life and her dream.
---
"Yes!"
Her answer rang out clear, unwavering.
Aizen looked at her, and his smile softened—warm, gentle, comforting.
Even his voice felt like a calm spring breeze:
"Then, Yakumo-san… prepare yourself accordingly."
Yakumo trembled with emotion.
She slid off the operating table and knelt deeply on the floor, forehead nearly touching the ground.
"Thank you, Aizen-sama!"