The underground laboratory was nothing like Kakashi had imagined.
There was no damp air, no rot, no sense of decay. Instead, the corridors were dry and brightly lit, though their winding, serpentine layout made it easy to lose one's sense of direction.
With a soft hiss, the lab doors slid open. Inside, medical-nin wearing protective masks moved briskly between workstations. Before Kakashi could take another step, a guard stepped into their path.
"Yoru-sama," the man said politely, extending an arm, "the person with you must sign a confidentiality agreement."
Yoru smiled and nodded without hesitation.
"That's fine."
He turned slightly. "Kakashi, go ahead."
Confidentiality agreements were only required for classified facilities or restricted briefings. Kakashi felt a jolt of surprise. This wasn't a private hideout. It was an officially sanctioned research site belonging to the village.
If this were truly illegal, he would never have been allowed inside at all, agreement or not.
As a jonin, Kakashi had clearance for sensitive matters, provided the proper protocols were followed.
"All right," he said.
He accepted the scroll and pen, signed his name, and pressed his fingerprint beneath it. Only then was he allowed to proceed.
As they walked deeper inside, Yoru spoke casually, as if they were simply touring a training ground.
"Orochimaru-sensei is currently affiliated with Root. You've served in ANBU, so you already know how these arrangements work."
Kakashi kept his expression neutral, playing his role.
"Then what exactly is being researched here?"
Yoru paused, then smiled apologetically.
"The core projects are classified. But the general purpose isn't."
He gestured around them.
"This facility focuses on cultivating limbs and organs. Improving transplantation techniques. Eventually, the goal is to grow replacements directly, rather than relying on prisoners or captured operatives."
At jonin level, organ and limb transplants weren't unheard of. Losing an arm or an organ in combat didn't have to mean retirement. Finding compatible tissue with chakra that wouldn't reject the host was standard practice.
Most of the time, those parts came from traitors, spies, or death-row prisoners. During wartime, even captured enemy shinobi were used. No one talked about it openly, but every major village accepted it.
Kakashi looked around.
Glass tanks lined the walls. Inside them floated arms, legs, even hearts, suspended in nutrient solution. The sight was clinical rather than bloody, but no less unsettling.
"Yoru… this is—"
Kakashi trailed off, his tone subdued. For a moment, he wondered if Yoru was trying to pull him into something deeper, something political. The recent actions of the Seventh Unit already made it clear that Orochimaru was sending signals to the village. Signals of intent.
Yoru noticed his hesitation.
After a quick glance around to make sure no one was paying attention, he slowed his pace so they walked side by side and spoke quietly.
"Kakashi, there's no choice," he said. "If nothing is done about your Sharingan, it'll keep draining your chakra nonstop. Until you fully adapt, you're barely functional. And even if you do adapt, your long-term growth will suffer."
It was the truth.
With an always-active Sharingan, Kakashi couldn't train normally. His only viable path forward was control. Extreme control.
A prodigy held back by a single eye.
And at this age, when most shinobi experienced their fastest growth, Kakashi was effectively stalled.
Looking at Yoru's apologetic smile, something warm stirred in Kakashi's chest. He lowered his head slightly.
"…Thank you, Yoru."
Yoru chuckled.
"Don't worry. I won't put you in a difficult position. Once your eye problem is handled, you won't need to concern yourself with the rest."
He spoke like an old classmate lending a hand, as if the bonds formed in the academy still mattered.
That only made Kakashi feel worse.
Against enemies, he never hesitated. Even against traitors from the same village, he wouldn't waver. But this time, he was deceiving a comrade.
At first, Kakashi had believed Yoru intended to draw him fully into Orochimaru's faction. It would have made sense.
The Hatake name still carried weight. The White Fang's reputation hadn't faded completely. Kakashi himself had become a jonin at twelve. Talent, lineage, connections. These were invisible assets, but to political players, they were invaluable.
Whoever gained Kakashi gained all of that.
Yet now, it didn't feel that way.
"Just let me handle the talking later," Yoru added with a wink. "Orochimaru-sensei isn't petty. You'll be fine."
To Kakashi, it didn't look like manipulation.
It looked like Yoru trying to keep him from being dragged deeper into muddy water.
Kakashi's placement in the Seventh Unit was, on the surface, recovery. Beneath that, it was a modest political investment, no different from recruits like Inuzuka or Aburame.
But the Uchiha and Hyūga were different. They had already chosen their side. Their bets were placed directly on Orochimaru.
Yoru, however, seemed determined not to push Kakashi that far.
And because of that, the weight in Kakashi's chest only grew heavier.