Chakra is a unique kind of power.
In a certain sense, chakra doesn't naturally exist in the Shinobi World. Its presence is due to the Ōtsutsuki clan, who used the Ten-Tails to forcibly merge and refine the world's energy into a unified form—chakra.
As a result, top-tier chakra can reach terrifying intensities. The chakra possessed by the Sage of Six Paths was so powerful that it even exceeded the spiritual energy currently controlled by Yoru.
That said, the chakra found across the Shinobi World today is an incredibly diluted version.
Still, no matter how diluted it becomes, the essence of chakra cannot be changed. It is the fusion of spiritual and physical energy—and it inherently contains a person's will, or more precisely, a "wedge."
The wedge of the Sage of Six Paths.
The wedges of Indra and Asura.
In the original timeline, Indra and Asura used this high-level chakra to reincarnate across generations. While it wasn't identical to the Ōtsutsuki's direct soul transfer through wedges, the principle was similar.
After all, Indra and Asura were also descendants of the Ōtsutsuki.
Each generation's reincarnated vessel would gradually become more and more like Asura in chakra, body, and thought—until the transformation was complete. In the end, they became a full recreation of the original Asura, effectively resurrecting both Asura and Indra through an alternate method.
"You should now understand what our goal is for the future," Yoru said calmly. "In a sense, even the Sage of Six Paths was one of them."
"They possess an extremely special power: replicating and digitizing themselves, then implanting that data into others, ultimately using the target's body to achieve their own resurrection."
Yoru explained in a matter-of-fact tone. This concept wasn't hard to grasp. Within the Soul Society of Kirigakure, all captains had access to learning materials, and Yoru had intentionally included information on the Ōtsutsuki, particularly their method of achieving immortality—through wedges.
"While such words may seem cruel, that is the reality."
Uzumaki Kushina's fists were clenched tight, her entire body trembling. Yoru watched her silently.
"As time passed and Naruto grew older, the compressed "file" hidden inside his body would begin to "decompress" piece by piece. Once the full dataset was unlocked, the vessel's body would be overwritten by the Ōtsutsuki's data. The original person—the vessel—would vanish completely. That would mark the full resurrection of the Ōtsutsuki within Naruto's body.
This process would be silent and subtle. Even Naruto himself wouldn't notice it happening. Over time, his personality and self-awareness would be replaced entirely. In the end, he would become nothing more than the embodiment of the chakra being awakened inside him."
Yoru's words were clear and precise.
Kushina said nothing.
There was no visible explosion of rage, no scream, no tearful outburst. But her nails had pierced into her palms so deeply that blood dripped from her clenched fists.
She was a mother.
A mother who had only recently given birth, who had placed all her hope and dreams in her child. To suddenly learn that her son would one day be used as a tool for someone else's resurrection—that pain was worse than death.
"Why…"
Kushina stared at Yuki Yoru, her aura surging like a volcano about to erupt.
"Why Naruto? Why him?!"
"A very good question."
Yoru nodded slightly. "Based on everything we know, descendants of the Sage of Six Paths are more likely to be chosen as vessels. That includes clans like Senju, Uchiha, Kaguya, and Hyūga—their chakra makes for ideal vessels."
"Statistically speaking, Naruto should've had low odds of being chosen. But not zero."
"Minato was from a civilian family. But you weren't. The Uzumaki clan is closely related to the Senju—a branch family. You're a descendant of the Sage."
"So the reason lies with you. But even that doesn't quite add up. A mixed-blood should be inferior to pure-blood… shouldn't they?"
Yoru's tone lightened, almost joking.
"But now I'm curious—why did you and Minato name your son 'Naruto'?"
"W-what do you mean by that?"
Kushina paused, confused at the sudden change in topic.
"Oh, nothing. That name just reminded me of something," Yoru said, eyes narrowing. "I hope it's not what I think it is."
"…It came from one of Master Jiraiya's novels," Kushina answered after a moment, with a touch of pride. "Minato named Naruto hoping he would grow up like the main character—persevering, strong, responsible. A true man."
That answer made Yoru's expression shift slightly.
"So it was Jiraiya…"
"What do you mean by that?!"
"Heh."
Yoru chuckled and continued, guiding Kushina toward the truth.
"Jiraiya had two disciples in his lifetime. One was Minato Namikaze. The other… is the leader of the Akatsuki—the very man who attacked the Five Kage Summit in the Land of Iron."
"As Minato's wife, surely you know why Jiraiya chose him as his student."
"Because of status? No—Jiraiya was one of the Sannin, a disciple of the Third Hokage. People were begging to learn under him."
"Because of talent? No—Minato was a genius, but when he first graduated, he hadn't shown his full potential. The teacher-student bond alone wasn't strong enough to warrant such favor."
"The real reason… is because Jiraiya believed Minato was the…"
"…Child of Prophecy," Kushina whispered.
"Exactly."
Yoru's smile was faint but knowing.
"The toad from Mount Myōboku predicted that Jiraiya would find the one destined to bring either peace or destruction to the Shinobi World. He thought Minato was that person."
"But he was wrong. Minato died."
"The leader of the Akatsuki isn't the one either—I crippled him in the Land of Iron. Even if he recovers, he's no longer a threat."
"I hate those toads, but one thing's certain—that prophecy has never been wrong."
Yoru looked directly at the stunned Kushina.
"But Jiraiya is dead now. He won't be taking on another disciple."
"So tell me—where is that 'Child of Prophecy' now?"
"…Naruto."
"Perhaps that's why there's a special chakra spirit hidden inside his body."
With that, Yoru casually planted the seed of suspicion between Kushina and Mount Myōboku.
Even though his true enemies were the celestial Ōtsutsuki, Yoru harbored no fondness for those "dead frogs" either.
That damned toad had been scheming since the days of the Sage of Six Paths. If Yoru believed it wasn't plotting something, he'd be a fool.
No matter where you went—everyone had their own agendas. Whether it was the toads or Hamura Ōtsutsuki's legacy, everyone had stakes in the Shinobi World.
And Yoru had no intention of letting any of them win.
Kushina's face twisted with unease. Her brows knit together in silence.
She hadn't signed a summoning contract with Mount Myōboku, but she was deeply connected to them. Her husband, her husband's teacher, and even her own son had signed the toad summoning contract.
(Yes—Naruto had done so during the Nine-Tails' attack.)
What role had Mount Myōboku played in all this?
Did they know nothing about the chakra spirit inside Naruto?
Or were they involved?
Was this a prophecy they merely foresaw… or something they actively orchestrated?
Could it be that everything—from Jiraiya taking Minato as a disciple, to all the events of the past few decades—had been one massive conspiracy?
Had it all been for the resurrection of that entity hidden within Naruto?
"No. I won't allow it. I refuse to let Naruto become someone else's vessel!"
Kushina roared, turning to storm out—only to be blocked by Yoru.
"And what are you going to do?"
He looked at her calmly. "March into Konoha and announce to the world that you're alive? Slap the village elders in the face and then take your son back to raise yourself?"
"That would definitely be a very 'Kushina' thing to do."
"But what then?"
"That chakra spirit inside Naruto—you can't remove it."
Yoru's words made her freeze in place.
"Not even you?" she demanded.
"Not at the moment," he admitted with a shrug. "I'm not ashamed to say it."
In truth, it wasn't that Yoru couldn't remove the Asura chakra—it was that he didn't dare provoke the Sage of Six Paths.
He remembered all too clearly the terrifying presence that had emerged during the Nine-Tails' attack.
At this point, he simply wasn't strong enough to take on the Sage himself.
"Don't act recklessly, Kushina. I understand how you feel—any mother would. But we're talking about plans laid over centuries. You can't just bulldoze them on a whim."
"Some things take preparation."
"…"
Kushina remained silent.
Yoru wasn't in a rush.
He had told her all this for a reason—not to make her throw a fit and storm into Konoha, but to use her identity as the "Mother of the Child of Prophecy" to shake things up in the future.
If she charged in now, it would only mildly irritate the Sage and that damn toad—without changing a thing.
"…What should I do?" she finally asked, calmer now.
"Nothing. If you want to help your child, then master your power. Focus on understanding your strength."
Yoru's voice was soft but resolute.
"When war breaks out in the future, you'll need to be able to stand in front of him. To shield him from everything."
"As for now, don't worry too much about Naruto. The chakra erosion is real, but it takes time. And with me around, they won't succeed so easily."
"…Alright."
Kushina nodded firmly, eyes burning with resolve.
As a mother, she was ready to give everything for her child.
She had given her life during the Nine-Tails' attack.
And now…
She was willing to offer even her soul.
—
To protect her son, Kushina continued learning to harness the power of a Shinigami.
Yoru stood nearby, occasionally offering pointers. In the absence of combat, his shadow clone could remain indefinitely.
His real body, however, was currently on Kirisumi Island.
"To have a Shinigami devour the power of a Hollow…"
Uzumaki Hiromi muttered as she observed the scene below. "Can that really be done?"
Shinigami and Hollows were similar in some ways—they both used spiritual power to stimulate the soul. But where the Shinigami process was stable and orderly, Hollows were born from overwhelming emotion, fusing that chaos into their power.
It was like order versus chaos—two opposing forces.
Could they really be merged?
Even with Uchiha Shisui's immense spiritual energy and the Rinnegan—a top-tier power—this was a warped fusion of opposing aspects of the soul. Could he really endure it?"
"Yes."
Yoru's reply was calm—but filled with absolute confidence.
As if this wasn't some wild gamble, but a predetermined outcome.
As long as the steps were followed—it would succeed.
Hiromi didn't know where Yoru's confidence came from. She was the core figure behind all of Kirigakure's current Shinigami experiments, and the most knowledgeable person about Kirigakure, or rather, Yoru's current understanding of Shinigami, Hollows, and even the still-developing Quincy, without exception.
Almost all newly created Shinigami had passed through her hands, and she was responsible for various researches within Hueco Mundo.
She understood Yoru's logic to an extent.
Just like the Rinnegan required "dividing one god into Yin and Yang, then fusing opposites into one to grasp all phenomena," the fusion of two diametrically opposed forces was a valid path to evolution.
But this? Merging Shinigami and Hollow powers now?
It was far too soon. She couldn't see any chance of success.
But Yoru…
Hiromi looked down at Uchiha Shisui with narrowed eyes.
If Yoru said it would work—then it would work.
—
"…It hurts…"
On Kirisumi Island, Shisui was in agony.
After devouring that Adjuchas, he felt like a fire had ignited inside him—yet he was shivering from the cold.
The physical symptoms were secondary. The worst part was his mind.
A storm of violent, evil, twisted emotions was flooding into his brain.
"It's unbearable! This Shinigami-Hollow fusion—it's torture!"
"I was the Uchiha prodigy! Konoha's hope! And now here I am, used like a breeding tool in Kirigakure. Sure, some parts were fun—but the humiliation…"
"He stole my Mangekyō! Took everything from me! Tormented me with life-or-death experiments—body, soul… I was a person, and now I'm nothing but a broken ghost! Damn you, Yuki Yoru! Damn you!!"
His mind cracked.
A deluge of warped, furious memories erupted. The kidnapping, the theft of his Mangekyō, the experiments…
Everything he'd suffered played in his mind—and under the influence of the Hollowfication, the rage was magnified a hundredfold.
His Rinnegan was bloodshot, and the searing pain in his body pushed him over the edge.
"AAAAAAHHHHH!!"
Blood-tears streamed down his cheeks.
Kneeling, Shisui let out a tortured scream. His soul and body were breaking.
Yoru and Yumi watched from above.
Suddenly, a faint glow lit up in Yoru's eyes.
"…It's happening."
"What?" Yumi asked reflexively—and then gasped.
Right before her eyes, strange white spiritual matter began to pour from Shisui's body.
It crawled up his face, hardening into a monstrous white mask.
His limbs twisted. His skin morphed. Even his hands and feet warped into something beastlike.
Uchiha Shisui…
Had undergone Hollowfication.