"I've already extracted the chakra and sealed it inside this scroll," Kai Uchiha said, his voice steady, though Aya Hyuga found his tone as grating as ever.
Still, she didn't argue. Handing over the sealing scroll, she replied evenly, "I'm not sure if it will work, but I did as you asked."
Whether tailed beast chakra could be preserved this way, Kai wasn't entirely sure. Nor could he tell if Aya truly understood the implications. Yet she carried out his instructions with eerie precision.
Taking the scroll, Kai frowned. Chakra without a living medium is like rootless duckweed—unstable. Even if it came from a tailed beast, preserving it without a proper vessel was a gamble. But experimentation demanded risks.
Could it be integrated into his body? That idea sounded reckless, even to him. The jinchūriki system existed for a reason—without a compatible host, tailed beast chakra was lethal. Even full jinchūriki often died if the beast was extracted. He wouldn't risk becoming another corpse for the sake of ambition.
Aya suddenly spoke again. "While repairing Nohara Rin's body, I noticed something unexpected. The tailed beast's chakra greatly enhanced her cellular activity—far beyond what I anticipated."
Kai raised an eyebrow. "Are you suggesting we leave it inside her?"
"Not suggesting anything," she answered coolly. "Just stating an observation. She doesn't matter to me—I follow your orders, nothing more."
Kai's eyes narrowed. If Rin's body still carried residual chakra from the Three-Tails, it could complicate his plans. He originally ordered Aya to extract it, so what was the point if they were keeping it?
Besides, Rin had already served her purpose in his broader strategy—either as bait for Obito or a tool to manipulate remnants of Uchiha Madara's legacy. She didn't need that chakra anymore.
He slipped the scroll into his cloak. "Fine. We'll decide what to do with it later. How's the rest of her body?"
Aya's expression turned more serious. "While repairing her heart, I noticed something odd—residual chakra signatures. At first, I thought it was damage from Hatake Kakashi's Chidori, but that's not it. There's a seal—subtle, but definitely a curse mark."
Kai froze internally but kept his tone even. "From Kirigakure?"
Aya nodded. "Likely. You mentioned in your report that she was captured by the Hidden Mist, right?"
"Yes… she was made a jinchūriki and likely set up as a bomb to destroy Konoha from within," Kai confirmed. "That seal must have been the trigger. She let Kakashi kill her to stop it. She couldn't say anything—probably part of the curse's conditions."
That curse mark changed things. Kai had claimed in his report that Rin's body was incinerated along with the other corpses. If word got out that her body was intact—and had a foreign seal on it—it could trigger political fallout. Aya might be more dangerous than she appeared.
She gave him a knowing glance, clearly suspicious but not pushing. Whatever Kai was hiding, she seemed willing to let it lie—for now.
"So?" Kai pressed. "How long will the repairs take?"
"Removing the curse seal will be delicate. I also need to study more—my fūinjutsu isn't advanced enough. And I'll need materials to keep her body from decaying in the meantime."
"I'll get them," Kai said. "Focus on the work."
Aya nodded, then fixed him with a steady gaze. "But isn't it time you told me what this is really about, Kai-kun?"
Kai had expected that. He smiled faintly. "I thought you'd ask. Come with me—I'll show you."
He led her down the hall of his private facility. Once a humble hideout, it had grown over the years—expanded with corridors, rooms, and research equipment. Hidden near the Uchiha district and deep in forested land, it was as secure as it was secret.
The deeper rooms were eerily silent. Aya's steps echoed faintly as they entered a chamber lined with advanced life-support equipment. In the center floated a familiar figure: Uchiha Yuchi, suspended in a tank of glowing nutrient fluid.
Aya flinched slightly but kept her composure. She had seen this man before—seen Kai carve him up for experimentation. She hadn't liked it, but she hadn't interfered either.
"So, you're going to tell me your real goal?" she asked.
"Part of it," Kai said, stepping beside the chamber and forming a single seal. "Tell me, Aya—do you really think the Byakugan or Sharingan are the true limits of our clans?"
"Aren't they?" she said dryly. "Kai-kun, I didn't think you were one for superstition."
"Not superstition. History." He looked her in the eye. "Why do you think the Uchiha and Hyuga were feared during the Warring States era? Reconnaissance alone couldn't dominate a battlefield."
Aya said nothing. As a branch member of the Hyuga, she had never seen clan archives—certainly not from centuries ago. But Kai wasn't just anyone now. He had risen far above what he once was.
"I've read the scrolls," Kai said quietly. "Before the clans joined Konoha, the Hyuga wielded a taijutsu style called Shinkūken—a vacuum fist technique attributed to Kaguya Ōtsutsuki herself."
Aya frowned. "That name… sounds like the kind of thing the elders would deny even existed."
"Exactly. They don't want you to know what your bloodline was capable of. The same goes for the Uchiha—our eyes haven't reached their peak either. The Mangekyō Sharingan? It's not the end. It's a stepping stone."
Aya watched as Kai's chakra flared. The tank hummed, and Yuchi's eyes opened slowly. But they weren't ordinary Sharingan.
Aya's breath caught. The pattern in his eyes was unlike anything she'd seen—jagged, dangerous, symmetrical in a way that disturbed her instincts.
"That's…" she whispered.
"The result of forcing evolution," Kai said calmly. "A Mangekyō forged not just through trauma, but design. Aya, if we combine the power of our clans… we might reach something beyond bloodline limits."
Aya Hyuga's expression was unreadable—but Kai knew her well enough to see the intrigue behind her silence.
And that was enough. For now.