Chapter 7: Spirit Transformation Technique, Possession Technique
Inside the Hokage's office, smoke curled thick in the air.
The Third Hokage leaned back in his chair, one hand resting on the desk, the other holding a smoking pipe between his lips. As he listened to ANBU agent Yoru's report, he exhaled slow streams of smoke.
When he heard that Captain Baku suspected Kimura Yō had most likely been killed and turned into a human puppet, the Third Hokage paused mid-inhale. Then he drew deeply from his pipe again. Though his eyes remained calm, a flash of astonishment passed through them—followed by barely restrained fury.
Truthfully, the Third had already suspected Kimura Yō might be dead.
From the moment Minato described his interactions with Yō, it had been clear that the boy had most likely been eliminated.
After all, if it were just genjutsu control, what valuable intelligence could a child still in the Ninja Academy offer? There would be no need.
But posing as a child, using that identity as a springboard to infiltrate Konoha's shinobi system? That was another matter entirely.
So, what Minato encountered today wasn't the real Kimura Yō, but an enemy spy using some sort of transformation jutsu to impersonate him.
However, what the Third hadn't anticipated at all—was that Kimura Yō hadn't just been impersonated, but had been killed and turned into a human puppet.
And that puppet had brazenly continued attending the Ninja Academy.
That was a blatant insult to him—and to all of Konoha.
Unforgivable.
Once they found that spy, the Third swore to have them experience the full force of Konoha's ANBU interrogation cells. Only then would his anger be quelled.
Just as he was thinking this, Yoru continued his report. He relayed that the Aburame agent's insects couldn't find any chakra threads around Kimura Yō and described the various abnormalities Baku had observed in the boy's body. He ended by asking whether they should continue expanding the search for the infiltrator or directly apprehend the target.
Upon hearing this, the Third's expression grew grave.
He trusted Aburame's skills. Not even the thinnest chakra threads could escape the senses of insects that feed on chakra.
If Kimura Yō had been turned into a human puppet, there would have to be a chakra thread controlling him.
But if no such threads were present, that ruled out the puppet theory.
Which left only two possibilities:
Either this "Kimura Yō" was still a transformed spy—
Or Kimura Yō really had died, and his corpse was being controlled by some unknown means that wasn't puppetry.
Between the two, the first was manageable.
But the second…
That would be a nightmare.
An ability to control corpses instantly brought to mind forbidden techniques like Edo Tensei.
If the enemy had mastered a jutsu even remotely like Edo Tensei, the threat to Konoha would increase exponentially.
Baku had reported that Kimura Yō's body was cold—indicative of a corpse.
The Aburame insects had sensed no chakra being naturally released from the body, which all but eliminated the possibility that the target was still alive.
No matter what transformation technique was used, a living person couldn't fully suppress the natural leakage of chakra.
Therefore, Kimura Yō was, in all likelihood, a corpse.
Which meant the Third was facing the scenario he least wanted to consider: an enemy using some unknown method to control the body of the dead Kimura Yō.
As for that method—the Third quickly dismissed Edo Tensei.
That technique was created by the Second Hokage and was exclusive to Konoha. It was currently under his own custody, and everyone who had ever studied it was accounted for. There was no way Kimura Yō was a product of Edo Tensei.
Then there was the Yamanaka clan's Mind Transfer Technique, which could also manipulate corpses, but only those who had just died. It certainly couldn't keep one active for over a week.
So it couldn't be that either.
What other jutsu could control a corpse—allowing it to move like a living person, refine chakra, and even retain its memories?
"Hm… Wait. There is one such technique."
"Spirit Transformation Technique!"
In an instant, a once-famous secret technique from the Warring States period surfaced in the Third's mind.
This was a technique once preserved by the Second Hokage and passed down in Konoha. It wouldn't be surprising if others in the shinobi world had inherited it too.
The more he thought about it, the more convinced the Third became that Kimura Yō had fallen victim to a possession-type jutsu related to the Spirit Transformation Technique.
(Note: In this setting, Spirit Transformation Technique is assumed to have originated in the Warring States period and is not exclusive to Konoha.)
The Spirit Transformation Technique allowed one's soul to manifest physically, enabling a range of jutsu that targeted the spirit.
Killing someone's soul, taking over their body, reading their memories—these were the basic capabilities of the technique.
But the Possession Technique—that was its pinnacle, the very reason the technique had been created.
As its name suggests, the Possession Technique allowed a shinobi to seize another person's body with their soul, effectively granting them immortality by permanently inhabiting a new vessel.
If that was what had been used, it explained everything about Kimura Yō's condition.
Kimura Yō's soul was dead, but his body lived on—controlled by the soul of a hidden enemy.
The corpse felt cold because the enemy soul hadn't fully acclimated to the new vessel—making the body feel like that of a dead person.
That was a side effect unique to Spirit Possession.
Until the soul fully merged with the body, it would remain unnaturally cold.
As for the total lack of chakra leakage, that too could be explained as a side effect of the possession process.
The Third didn't know the technique himself. Few in history had mastered it, and even less was known about it in detail.
Still… there were flaws in the theory.
First, during the adaptation phase, a possessed body couldn't handle prolonged, high-output chakra refinement. That would worsen the rejection between the soul and body, extending the adjustment period.
But Minato had said Kimura Yō had spent the entire day rapidly refining chakra—which directly contradicted the behavior expected during possession.
Second, even though the Possession Technique allowed a soul to continue living in another body…
That body would eventually reject the soul, leading to both the body's collapse and the soul's dissolution.
This rejection was irreversible. The longer the possession lasted, the worse the conflict became. In most historical cases, ninja who performed spirit possession died within a year.
That was what the Third couldn't understand: what value did Kimura Yō hold that would make a master of such a powerful and dangerous technique sacrifice their life just to possess him?
It was known that anyone capable of using this technique was at least elite jōnin-level in power.
And unlike other elite jōnin, these spirit-users could kill with a single hit if their enemy lacked mental defenses.
In history, those who wielded the Spirit Transformation Technique were terrifying and infamous across the ninja world.
So why would such a powerful shinobi use their life to possess a mere child—for a year at most?
It didn't make sense.
The technique itself, whether for killing or espionage, had far more utility than this.
So why?
The Third set down his pipe, brows furrowed, unable to figure it out.
Put himself in the enemy's shoes—he wouldn't sacrifice his life to possess a six-year-old boy like Kimura Yō.
If it were a renowned ninja, perhaps a disciple of his or someone close to Konoha's core, it might be worth the risk.
But Kimura Yō? An orphan with no special talent? He had no access to any classified Konoha secrets.
Even his own disciples didn't know that much.
So it simply wasn't worth it.
Unless—
Unless the possession no longer caused death.
Yes… no death!
The Third muttered this inwardly, his pupils shrinking suddenly as a realization struck him.
There was one possible explanation.
The Possession Technique had been perfected.
The version of the Spirit Transformation Technique in use no longer caused bodily rejection. The user had achieved true immortality.
It wasn't impossible. The Third had never underestimated the creativity of geniuses in the ninja world.
If… no—if the Possession Technique had truly been perfected—
Then everything would make sense.
Only then would it explain why someone would target a six-year-old orphan with no talents—because the body could now be used permanently.
The Third's eyes gleamed with growing intensity.
A technique for eternal life—who wouldn't desire such a thing?
(END CHAPTER)