A few days had passed, and though Kairi no longer felt physically fatigued, he could still sense lingering aftereffects. Once that faded, he'd know the recovery window of his current training cycle.
Of course, this was only possible because he lived in the world of Naruto. Here, even ordinary people possessed far superior physiques compared to his previous life. Had he pushed himself this hard in his last world, he probably would've broken down completely.
Then again, without the foundation of strong spiritual energy, he wouldn't have been able to push himself like this to begin with. Kairi knew himself well his willpower hadn't been anything remarkable in his past life.
Over at the academy, nothing particularly noteworthy had happened. Iruka continued leading the class through basic training drills and had just begun covering the fundamentals of chakra. For Kairi, though, most of it was a waste of time. He'd already finished reading the material on his own, and the training pace couldn't keep up with what he'd set for himself.
But that made sense classes had only just started, and Iruka was probably focusing on getting everyone caught up with the basics. Eventually, they'd be allowed to train more freely.
Now that he'd gone through the textbook, it was finally time to attempt chakra extraction. Since this was his first time, Kairi made sure to wait until Sina was home, just in case something went wrong.
Even though extracting chakra wasn't supposed to be dangerous, you could never be too careful.
"Mom, I'm starting now," Kairi said, sitting cross-legged on his bed. Technically, posture didn't matter for chakra extraction, but with someone watching, it felt appropriate to look the part.
"Alright. Don't worry, sweetie. I remember it being pretty safe," Sina said, cheering him on.
"I know." Kairi nodded. He just wanted to be cautious if he fainted in the middle of it, someone needed to be around.
Following the instructions from the book, Kairi began to focus on sensing his physical energy. He'd actually tried sensing it before and found it relatively easy. This time, with experience on his side, it felt even more natural.
Previously, he'd stopped short of extracting anything. But now, with Sina beside him, he felt reassured enough to proceed. He carefully guided his spiritual energy to merge with the physical energy flowing through his body, initiating the chakra formation process.
There were no surprises. The extraction succeeded almost immediately. Concentrating, Kairi directed the newly formed chakra toward his hand, watching as the familiar blue energy shimmered faintly into view.
"To think you'd succeed on your first try… Kairi, you're amazing!" Sina gasped in surprise. While chakra extraction wasn't particularly dangerous, succeeding on the first attempt was still rare. It made her wonder if her son was truly gifted. That thought filled her heart with joy.
She made a decision then and there tomorrow after work, she would ask her old teacher for help in acquiring the Shadow Clone Technique as a surprise for Kairi.
"It wasn't that hard, honestly," Kairi replied, a little surprised himself at how smoothly it had gone. Maybe it had something to do with his spiritual strength? Either way, it seemed his talent was decent. The real test would come with ninjutsu.
He wondered about his current chakra reserves. They felt decent, but without any frame of reference, he had no way to judge where he stood.
Lost in thought, Kairi didn't even notice his mother sneak up until she pinched his cheeks from behind.
"Come on! You just succeeded at extracting chakra you should at least smile a little!" she said teasingly.
Caught off guard, Kairi could only offer a forced smile. It wasn't exactly heartfelt, but Sina was satisfied.
"That's more like it. You're still just a kid, so don't go walking around with that serious face all the time," she chided gently.
Kairi sighed. It wasn't like he was expressionless he was just thinking.
Eventually, he escaped her playful grasp and returned to his room. He continued practicing chakra extraction not because he needed more chakra, but to get better at doing it smoothly.
Ideally, he wanted it to become second nature something he could draw on instinctively without deliberate effort.
As for what to do with the chakra once extracted... he didn't know any jutsu yet, and it felt wasteful to let it dissipate. Maybe he could use it to train control?
Climbing trees or running up walls was an option, but those could get noisy if he slipped and fell especially with his mother resting in the next room. Better not risk disturbing her.
Then there was shape transformation or nature transformation...
Nature transformation was out he didn't even know his chakra affinity yet. That left shape manipulation. He could start by trying to mold the chakra into a sphere the simplest form.
Kairi extended his hand and began guiding the chakra outward. But as soon as it left his body, it scattered instantly, slipping through his control like mist on the wind.
He frowned but didn't give up. Nobody succeeds on the first try.
So he repeated the process: extract, attempt, fail, and repeat again.
Soon, his chakra was completely depleted. From the way things went, Kairi estimated that he could likely extract his entire chakra reserve in one go if he really tried. That was because chakra extraction was determined by spiritual energy and his spiritual strength was abnormally high.
Which only highlighted the imbalance his chakra pool was nowhere near what it should be, given his mental reserves.
Still, he made some progress with the shape manipulation. Even though the chakra dispersed quickly, he could now faintly sense a lingering connection between himself and the energy. Controlling it through that thread was difficult, but the thread existed and that was a start.
Feeling drained, Kairi called it a night. Tomorrow would be even more important.
He needed to find Iruka not only to get an assessment of his current chakra reserves but also to try requesting early access to the Clone Technique. Kairi was confident that he had enough chakra to handle it. As long as he demonstrated his ability, he believed Iruka would agree.
And if that didn't work, he could always ask his mother for the jutsu hand seals and then consult Iruka for guidance on how to perform them properly.
With that plan in mind, Kairi drifted off to sleep.
The next day, after class, he approached Iruka directly.
"Do you need something, Kairi?" Iruka asked with a curious look.
"Sensei, I've finished studying the chakra material on my own and successfully extracted chakra. I was hoping you could help me evaluate my current chakra level."
Iruka blinked. "You already taught yourself?"
As someone who prided himself on being a thorough teacher, Iruka had made it a point to learn about all his students. Kairi's mother had once been a genin, yes but from what Iruka understood, she didn't have the knowledge or ability to guide her son effectively. She only knew how to use chakra, not how to explain it.
Which meant Kairi had learned everything on his own within just a few days and even succeeded at extracting chakra.
Iruka didn't know why Kairi wanted his chakra level evaluated, but as a teacher, he always appreciated students who were both hardworking and talented.
"Of course," Iruka said with a smile. "I'd be happy to help."