After the funeral, Kai Uchiha returned to a relatively stable routine. His days consisted of reading at the library, training, and recording data on his Mangekyō Sharingan.
These peaceful days were fulfilling, but due to certain circumstances, Kai had to revise his schedule—particularly, the data recording could now only be done in the morning when the surroundings were quieter and privacy was assured.
Not long after Kakashi Hatake was discharged from the hospital, he began appearing more frequently. Perhaps it was because Minato Namikaze was too busy, or perhaps Kakashi had grown curious about Kai's progress with Chidori—after all, he had personally entrusted the jutsu to him.
However, Kakashi didn't dare approach the Uchiha compound. Being a non-Uchiha with a Sharingan in his left eye, he was acutely aware that his presence might not be welcomed by certain clan members.
One day, while avoiding Might Guy—who was overly eager for another sparring match—Kakashi wandered into an unfamiliar forest and coincidentally ran into Kai, who was training using shadow clones.
Since their paths kept crossing, Kai eventually adjusted his schedule and began training with Kakashi regularly. Though slightly inconvenient, it provided Kai with a sense of security.
With Kakashi's presence, any monitoring from Konoha's higher-ups would be less suspicious. And, more importantly, Kai gained a sparring partner whose combat experience and Sharingan use made him a valuable opponent. Despite Kakashi's eye only having two tomoe, his tactical experience was formidable.
Kai had always believed that no amount of solitary training could replicate the value of real combat. His own strength had grown rapidly—not just because of the unique method he used to awaken his Sharingan, but because of countless brutal battles on the front lines of the Third Shinobi World War. That power was bought with blood—sometimes, tragically, the blood of comrades.
Though he had learned many new techniques, Kai lacked a consistent and capable sparring partner. He wasn't ready to approach Fugaku Uchiha for help, so he had postponed the idea—until Kakashi conveniently showed up.
"Bang!"
With a sharp kick, Kai sent Kakashi sprawling. His eyes flared with the three-tomoe Sharingan, and for the first time, he realized he wasn't far behind Kakashi in terms of ability.
Kai's specialties were the Body Flicker Technique and surprise attacks, but in direct confrontation, those advantages were minimal. His sparring with Kakashi was nothing less than a straightforward clash of skill and instinct—a true "man's fight."
Still, Kai was aware that Kakashi wasn't yet fully accustomed to using the Sharingan. It made sense that he often lost.
"It's fine," Kai said as he walked over and extended a hand to help him up. "You're still not comfortable with the Sharingan. Your use of it is basic—you've barely tapped into its genjutsu or perceptive capabilities. Keep training."
"Thanks," Kakashi replied, accepting the hand. "The Sharingan drains me too fast. My chakra can't keep up…"
Because he wasn't an Uchiha by blood, Kakashi couldn't deactivate his Sharingan. The constantly active eye consumed chakra at a dangerous rate—especially for a young shinobi still far from his prime.
Moreover, even though his Sharingan only had two tomoe, its chakra drain was far greater than Kai's fully developed three-tomoe eye. It was a burden Kakashi had to endure alone.
"Just keep training," Kai said with a shrug. "There's no other solution."
What could he suggest? That Kakashi get a tailed beast? Or implant First Hokage cells like Danzo?
Ridiculous. Even Kai himself wouldn't consider sealing a tailed beast, and as for Danzo—his twisted body was proof of how torturous that process was. Without Orochimaru's assistance and relentless experimentation, Danzo would never have survived it.
In the entire shinobi world, no one could rival Orochimaru when it came to forbidden research.
"Yeah… the Sharingan is a chakra black hole for me," Kakashi muttered. He slumped down on a rock, pulling his forehead protector over his eye.
"Once your chakra control improves, maybe I'll teach you a few tricks about using it," Kai offered casually, then asked before Kakashi could respond, "By the way, where was your father's chakra blade made?"
"Thanks, Kai," Kakashi said, pausing a moment before replying. "As for my father's blade... I'm not really sure where it was forged. Why, are you looking for one?"
"Yeah," Kai nodded. "I'm looking for a chakra-compatible weapon. Ever since you taught me Chidori, I've had a few ideas."
Of course, Kai wouldn't admit his true motive: he didn't want to get close to enemies again. His brutal encounter with Loess—a powerful Iwa-nin—had taught him a painful lesson. One punch had nearly ended him.
Though Kai had studied kenjutsu extensively, most standard weapons sold in Konoha couldn't withstand the intensity of his chakra. They would shatter after only a few uses.
That's when Kai remembered Kakashi's short sword. Aside from the Kusanagi blade Orochimaru gave to Sasuke, it was one of the few known weapons that could reliably channel chakra.
As for Orochimaru—Kai had no intention of contacting him. He'd seen the man at a recent memorial service, standing alongside a young Uchiha Itachi. It might've been the perfect chance to make contact, but Kai declined. Orochimaru was dangerous. And with rumors of his eventual defection already swirling, Kai didn't want to get entangled.
Public opinion on Orochimaru had grown increasingly divided. His loyal followers condemned the rumors and silenced dissenters, but accusations of human experimentation and disappearances of civilians and ninja alike continued to spread.
Kai didn't take sides, nor did Orochimaru offer any defense. Perhaps he was too proud—or simply didn't care.
With the Third Hokage reportedly considering retirement, the atmosphere among Konoha's leadership had become unstable.
"A new jutsu idea… and a sword, huh?" Kakashi mused aloud as Kai drifted into thought. "Maybe I can help with that."