"Kamui, huh…"
Amamiya Kenichi held a single eyeball up against the light, studying the faint tomoe pattern within.
On the surface, it was just a three-tomoe Sharingan.
But he knew better.
This wasn't just a three-tomoe.
It was a Mangekyō Sharingan in disguise.
Kakashi's eye.
The one he'd quietly taken on the night of the Nine-Tails' attack.
A week had passed since Namikaze Minato's funeral.
Konoha had returned to its routine with terrifying speed. Missions resumed, shops reopened, the village's daily noise slowly drowned out its grief.
The Fourth Hokage—
The hero who traded his life for the village—
Was already fading into background conversation.
And no one knew he'd left behind a newborn son.
Kenichi spun the jar between his fingers and exhaled.
"This isn't the time to implant it yet," he muttered.
Kamui's private dimension was amazing. A perfect lab, perfect vault, perfect escape route. He'd seriously considered using it as his personal research base.
But there was a problem.
Or rather, another owner.
Obito.
"As long as that guy is still alive, sharing a space with him sounds like a really stupid idea."
So for now, the eye stayed preserved.
Besides, there was the cost to consider. Kakashi's body had clearly shown what happened when a non-Uchiha forced a Sharingan to stay open all the time—
His chakra reserves were constantly being bled dry.
Kenichi already had plans for this eye.
First, research.
Why did using Mangekyō techniques consume "eye power"?
What was that, exactly?
If it were just physical damage to the retina, the pattern of degradation should look different.
Only once he'd mapped it out would he consider slotting Kamui in—test a few times, gather data, and then decide how to weaponize it.
Second…
He wanted to save it for a gift.
"One day, when I finish building a proper fuel-air bomb…"
Kenichi's lips curled slightly.
"I'll embed a little biological recognition mechanism inside and toss this eye in as the key."
Then, when Obito reached out with Kamui and touched that weapon—
Boom.
"I wonder if he'd feel moved," Kenichi murmured. "After all, it's a present from an old friend~"
He set the jar back in its case and looked out over the village.
Peaceful. Orderly. Calm.
Konoha was busy repairing its defenses, housing its orphans, rebuilding what the Nine-Tails had smashed. Orochimaru, for his part, had been enjoying something close to… good days.
Hiruzen needed him.
Root had been "quietly" sending grievously injured patients to their lab, and in public, Orochimaru often appeared at the Sarutobi compound delivering fine tobacco, smiling with the perfect demeanor of a filial disciple.
If you didn't know the truth, their relationship looked almost warm.
There were moments when even Kenichi wondered:
Is Sensei… not going to defect after all?
Is he actually going to stay?
Then the accident happened.
And everything snapped.
"Orochimaru! What the hell are you doing?!"
The voice boomed through the underground facility, raw and furious.
Kenichi didn't even have to look to know.
Jiraiya.
He turned just in time to see the white-haired sannin bursting into the lab, eyes wide with rage, as the stench of blood and antiseptic hung in the air.
On the surgical table, a half-finished test subject lay sprawled—
Once a village civilian, now a grotesque mess of flesh and wood.
Hashirama's cells had lost control again, swallowing the man's body from the inside out.
And Jiraiya had walked in right after Orochimaru tossed the corpse off the table.
Perfect timing.
If Kenichi had to guess, Root's external sentries had let Jiraiya pass on purpose.
After all, if they tried to stop him, it would be obvious who'd been sponsoring these experiments.
Much cleaner to let Jiraiya storm in, then go whisper in Hiruzen's ear.
"Oh? Jiraiya." Orochimaru didn't even look surprised. "Can't you see? I'm conducting research."
He lazily kicked the corpse toward him.
"Take a closer look."
That was the last straw.
Jiraiya's anger erupted.
People liked to joke later that Jiraiya wasn't "that strong"—
That he died too easily to his own student, that he wasn't as overwhelming as the legends claimed.
They were idiots.
He was one of the Three Legendary Sannin for a reason.
The moment the battle started, his first move was to blow off the ceiling entirely. Stone and dust exploded upward, revealing the lab to the open sky.
Then—
With a heavy thud, a massive toad manifested beside him.
Gamabunta.
"…Smart," Kenichi muttered, watching from the shadows.
Jiraiya wasn't just fighting.
He was making it loud.
Once the roof was gone, the scene below was visible from half the village. Konoha's shinobi would come running. ANBU would arrive. The Third wouldn't be able to sweep it under a rug and call it "a misunderstanding."
"Forcing the issue, huh?" Kenichi thought. "So the old man can't pretend not to see."
"I see you haven't changed, Jiraiya," Orochimaru said quietly.
His normally languid expression had sharpened.
A small snake slithered out from his mouth, writhed, and spat out a sword into his waiting hand.
Kenichi knew this battlefield wasn't for him.
He wasn't arrogant.
Whatever happened, Orochimaru's ability to escape was top tier.
Even if he couldn't win here, he could run.
And the moment ANBU and Root arrived, Kenichi's presence would only be a liability.
So at the very first clash between toad and snake—
He turned and ran.
Orochimaru noticed, of course.
He'd been subtly controlling the tempo from the start, blocking a few of Jiraiya's attacks just enough to leave Kenichi a clean escape route.
The moment Kenichi slipped past their line of fire, he sprinted down a side corridor.
He'd barely made it a few dozen meters before a masked man dropped into his path.
Root.
Kenichi recognized him immediately.
One of the handlers assigned to this facility.
Guard. Monitor. Leash.
"Danzō-sama's orders?" Kenichi asked calmly, but his muscles had already tensed.
He knew this man's rank.
Jōnin-level.
The masked shinobi's answer was succinct.
"Please die here."
No speeches.
No threats.
No mocking monologue.
Just movement.
He vanished, reappeared behind Kenichi in a blur of motion, blade thrusting straight through where Kenichi's heart should be—
And pierced only empty smoke.
A clone burst.
Somewhere in the trees, Kenichi's voice drifted out, equal parts annoyed and amused.
"Hey, hey… aren't villains supposed to talk more? You don't wanna at least explain your grand plan first?"
"…"
No response.
The Root ninja simply turned, weaved seals in an instant, and spat out a roaring Dragon Flame Jutsu toward the sound of Kenichi's voice.
The flames shredded branches and scorched bark—
But the boy was already moving.
Again and again, the forest lit up with flare and shadow, clones and feints colliding with silent, precise strikes.
Root operatives were a pain.
No ego.
No chatter.
No hesitation.
Just pure, efficient murder.
"Fine," Kenichi thought. "Let's test that technique."
He surged forward.
Months of training with Might Guy hadn't made him a taijutsu monster, but his close combat was no joke now. He could at least keep up for a short time.
Sparks flew as steel met steel.
The Root jōnin's blade thrust in, aiming for his ribs—
Kenichi's hand snapped up, catching the flat of the blade with his palm.
At the same time, something slender and invisible slid along his grip.
A needle.
Not metal—
But pure Yang Release chakra, compressed to the thinnest point he could manage.
He drove it straight toward the man's chest.
Specifically—
The lung.
"Let's see," Kenichi thought, eyes narrowing.
"Can an accelerated, guided cancer take down a jōnin…?"
Why study cancer first?
Obviously—because it's the closest thing to immortality we've found.
And why chase immortality?
…So you have enough time to do absolutely degenerate things with it, of course.
***********
Note: If you're interested, you can read up to chapter 99+ at patreon.com/nakai01. Don't forget to give a power stone for many bonus chapters.