Konoha.
The mountains behind the village.
After the third round of the Chunin Exams ended, Naruto followed Kakashi to the outskirts of the village, into a seemingly ordinary stretch of forest. This place, in fact, was where Kakashi had often trained in the past.
It didn't look like anything special, just a clearing surrounded by trees, but as Kakashi activated a concealed barrier, the scene before Naruto subtly shifted. What had appeared to be a normal training ground was actually a sealed-off space.
"Whoa… What is this place?" Naruto muttered, his expression turning serious.
Though the area within the barrier looked plain, he couldn't shake the strange feeling creeping through him, like some invisible pressure was warning him to stay out. It felt as though barging in recklessly might tear him apart in an instant.
"There are only seven days left before the final round of the Chunin Exams," Kakashi said calmly. "And improving enough in that time to surpass Hinata will be incredibly difficult. So… we're going to cheat time."
He pointed into the sealed space.
"This is where I used to train, a barrier where time flows differently. But you can't just walk into it. Because of the time dilation, if you force your way in, your body could be shredded."
As he spoke, his eyes shimmered.
His normal Sharingan morphed into the Mangekyo, then quickly into the Rinnegan.
With the Rinnegan fully activated, Kakashi's gaze glowed with power. In a blink, he swapped the space he and Naruto stood in with a portion of the barrier's interior.
In an instant,
They were inside.
The shift in sensation was immediate. Naruto could feel it. The outside world moved at a crawl compared to this place.
Ten seconds passed in here…
And only one second passed outside!
"You'll train here from now on," Kakashi said. "Time flows ten times faster in this space. You'll have at least two full months to use. I'll bring you food later. On the last day, I'll take you to another location for the final phase."
He fixed his glowing Rinnegan gaze on Naruto.
"Now then… the focus of this training, there's a power inside you, one you haven't tapped into yet. Our goal is to awaken that power."
Long ago, Kakashi had learned from Kaede that both Naruto and Sasuke were reincarnations of the Sage of Six Paths' sons, Asura and Indra.
After obtaining the Sage's Yin power himself, Kakashi became capable of perceiving the chakra of Indra and Asura lingering within Sasuke and Naruto. Still, he hadn't brought it up until now.
Because… it hadn't been time.
But now, after seeing what Kaede had done, personally guiding Hinata to wield Otsutsuki Hamura's chakra to such an extent that she could overpower nearly every jonin, he had a change of heart.
"If you're going to go that far, big brother… then so will I."
Kakashi muttered inwardly.
He'd long since accepted that he'd never surpass Kaede in this lifetime. But maybe, just maybe, his student Naruto could surpass Kaede's student, Hinata.
If Naruto beat her… then it would count as his win too.
He had to win against Kaede, just once!
=============
At that very moment,
Inside the Hokage's office in Konoha, Kaede was sitting on a sofa, deep in thought. Suddenly, his eyes flickered.
His Rinne-Tenseigan activated.
His gaze cut through the layers of space and fixed directly on the barrier in the mountains behind the village.
"…That guy Kakashi…"
Kaede's vision pierced through the time-altered barrier. Inside, he could see Kakashi and Naruto moving at ten times normal speed, like a fast-forwarded video.
That barrier was his Time Domain. Since it didn't require much effort to maintain, he'd kept it running constantly. There were only two ways to enter:
One, find him and have him pause the acceleration, enter the space, and then have him restart it.
Or two, do what Kakashi just did: use spatial manipulation to jump straight inside.
Very few people even knew the barrier existed. Only Kakashi, Uchiha Itachi, and a handful of others. To prevent any accidents, Kaede had added a second outer barrier to keep people from wandering in and getting torn apart by the time dilation.
At minimum, a person needed Mangekyo-level dojutsu to even detect the barrier, and breaking in required Six Paths-level power. In short, only Kaede and Kakashi had the qualifications to enter.
"…So you're trying to awaken Asura's chakra for Naruto?"
Kaede tilted his head, watching Kakashi work.
Clearly, Kakashi was trying to help Naruto tap into the dormant chakra of Asura. In other words, he was installing a cheat code ahead of schedule.
Kaede tapped his fingers against the table.
Asura's chakra wasn't as potent as Hamura's, but Kakashi, with his current Six Paths-level strength, did have the ability to guide Naruto in unlocking part of that power.
Still,
Wasn't this going a bit too far?
He's still just a Genin, Kakashi! Do you even realize what you're doing?!
Kaede almost opened the Gate of Yomi and dragged Kakashi out by force… but his hand stopped midway.
Because he remembered something.
Hinata hadn't even graduated from the Academy when I started teaching her to control Hamura's chakra…
In retrospect…
I might be even worse…
"…You're even using my time barrier to boost his training…"
Kaede sighed, rubbing his forehead.
If Naruto trained there for two months, he'd come out at age thirteen with strength probably at Kage-level. He might even rival, or surpass, the strength Itachi had when he awakened the Mangekyo at the same age.
He shook his head and decided not to interfere.
After all, Naruto was Kakashi's student. And truthfully, he was showing great potential. Reaching a powerful level at his age wasn't necessarily a bad thing.
However,
If Kakashi was going to hand Naruto such a massive power-up, then there was no way Kaede was going to neglect his own student.
He locked onto Hinata's location.
With a flicker, his figure vanished without a sound.
=============
Elsewhere,
In a quiet room, Hinata had just returned from the exam grounds. She was about to change and take a shower.
As she reached for her clothes, she suddenly sensed someone appear behind her, and reacted instantly with a sharp palm strike!
Crack!
Kaede calmly raised his left hand, blocking the blow. Her hand, wrapped in glowing blue chakra, clashed against his palm.
Zzzzt!
The chakra dissipated like waves crashing into an ocean, vanishing completely.
"K-Kaede-sensei?!"
Hinata's eyes widened as she realized who it was. She immediately retracted her hand, flustered and red-faced.
Kaede glanced at her briefly. The zipper of her jacket was half-undone, revealing a flash of white underclothes. Clearly, she'd been about to change.
Without saying a word, he averted his gaze and began walking out of the room.
"Come with me."
"Y-Yes!"
Hinata answered instinctively, even though she had no idea what this was about.
Not until she saw Kaede's back walking calmly toward the door did she fully realize what had just happened.
Her face flushed bright red.
Kaede must have used his space-time ability to appear beside her. She had seen him use it before. But the thought struck her:
What if he'd appeared just a little later…?
Her thoughts stopped cold.
She didn't dare imagine the rest.
Though ninjas were trained to disregard modesty during emergencies, if something like that had happened, she was pretty sure she would've fainted from embarrassment, and never dared face Kaede again.