A friendly fight.

[Time skip - 3 weeks, no jutsu]

Three weeks had passed, and their father still hadn't returned home. Kakashi didn't show it, but he was deeply worried. Eiji knew that Sakumo would come back, but he couldn't tell Kakashi as if he knew everything.

To pull Kakashi out of his dark thoughts and distract him, Eiji started increasing the difficulty of their training.

"Hey, Kashi-ni! Did you do all 500 sit-ups, 500 jumps, 500 push-ups, 500 punches, 500 kicks, and run 25 km?" I asked with my arms crossed, openly abusing my position as the older brother! Suck it up.

"I'm not a freak like you, Eiji-ni. How the hell do you manage to do double the training?" Kakashi couldn't believe what a freak his brother was; he was training more than Kakashi himself to get tired!

"Uhm, don't worry about those light workouts. When I meet some people, I'll raise the level of our training," Eiji commented vaguely, before smiling as if he were the embodiment of the devil.

"Come on, my little brother, I want to test a Taijutsu style I'm creating," Eiji said with a 'sweet' smile before entering a peculiar fighting stance, slightly crouched with his right leg forward, arms held in front of him.

"You're done with your weird Taijutsu?" Kakashi wasn't interested in the Taijutsu his brother claimed to be creating; he didn't believe it could be used in practical combat.

"Stop talking nonsense, it's not weird. You just need to have a flexible and agile body; our small bodies are perfect for this," Eiji said with a smile, almost completing his own signature Taijutsu.

Nodding at him, Kakashi quickly moved toward Eiji, attempting to land a punch.

Eiji crossed his arms, receiving the impact, creating a small distance between him and Kakashi. Using the force of the impact, Eiji quickly spun and kicked Kakashi in the shoulder, making him recoil.

Kakashi frowned; that kick hurt a bit, but nothing to worry about.

Eiji started hopping a little as he walked, his steps seemed extremely disjointed. Eiji quickly jumped toward Kakashi and delivered a low kick.

Kakashi jumped, thinking he evaded it, but Eiji gave a slight smile and used the centrifugal force of his body to kick Kakashi in the air. Kakashi took the impact, crossing his arms.

"First Taijutsu [Neraiken] completed."

Eiji quickly started hopping on the trees and used the branches to increase his speed, running to Kakashi's back at an extremely fast pace.

"Second Taijutsu [Kakato no Muton Ryuu] completed."

Eiji pulled Kakashi by the back of his shirt, which unbalanced him, and landed a kick to his belly, sending him straight to the ground, while Eiji used the force of the kick to spin on a branch and gracefully land on the ground.

Seeing Kakashi writhing on the ground in some pain from the fall, Eiji was quite satisfied. "Not bad, but I need more speed in the acrobatics." Eiji's two Taijutsus utilized his speed and flexibility to the maximum. That way, he could be in constant motion.

"Damn it, Eiji, couldn't you take it a little easier?" Kakashi groaned; the kick he received at the end of the technique caused him significant pain.

"No pain, no gain. Last week, you punched me in the face, and that hurt like hell," Eiji grumbled.

Now Kakashi averted his gaze, feeling a little guilty about it... for 5 seconds.

"What were those Taijutsus you used just now? We don't have them here at home, and they're not taught in the academy," Kakashi had never been interested in the Taijutsu his brother claimed to be creating, but he had to admit they were efficient.

"The first one is called [Neraiken].

Meaning: precise traces.

Classification: B.

By concentrating your chakra in your limbs, the practitioner releases a large amount of chakra through the chosen location in a short time and with high precision.

Obviously, he didn't use a large amount of chakra; otherwise, he could have killed Kakashi with just one strike to his back. Eiji was only able to perform such a technique thanks to his lineage, which allowed him to manipulate raw chakra more easily.

Most other people would have to possess excellent chakra control to use such a technique; it was similar to Tsunade's [Diamond Fist], with the only difference being that this technique didn't focus on a single impact point, so it didn't require as much control.

[The second is [Kakato no Muton Ryuu].

Classification: C.

Meaning: Tree Jumper Style.

By performing a complex set of acrobatics and jumps.

The practitioner can fight without staying in the same place. Using throwing weapons with high precision.

The practitioner corners their opponent with their completely disjointed jumps and gains the advantage of being particularly difficult to hit by any attack.

"As we're only training, and we don't have access to real kunai or shuriken, this style is limited for now. But in the future, I could implement traps or bomb papers. However, since my main combat weapon will be Kenjutsu, this Taijutsu will be extremely effective with my weapon, which uses extreme speeds to attack," Eiji explained his reasoning and looked at his brother.

"I WANT THAT!" Kakashi basically shouted in excitement.

"No, you don't," Eiji replied categorically.

"Why?" Kakashi whined.

"Hahaha, I was just kidding; of course, I'll teach you, all for my little brother. But before that, we have to master a technique to complete my Taijutsu." He spoke, looking directly into his brother's eyes.

"And what would that be?" Kakashi was eager.

"Tree climbing," Eiji said extremely seriously.

Kakashi: "..."

Eiji: "..."

"Are you kidding me? I already know how to climb a tree," he mocked his brother.

"Then climb without using your hands, just running without jumping," Eiji crossed his arms and challenged Kakashi.

"I can't," he mumbled softly.

"Huh? I didn't hear that," Eiji put his hand to his ear, mocking his brother back.

"I CAN'T, SATISFIED?" Kakashi roared in embarrassment.

"Yes, now I am," Eiji tried to hold back his laughter, but couldn't.

'Bastard,' Kakashi cursed internally.

"HAHAHAHA, don't worry, now listen. I'll teach you how to do it," Eiji said with a smile.

"You already know how to do it?"

"No," Eiji replied with the most innocent face he could muster.