Aizen went on, "Also, I don't want to watch the Uchiha clan's kenjutsu too closely. There's a chance their techniques might influence my own style. That's why I want guidance from someone outside the clan, someone with a different foundation."
Sakumo understood instantly.
He wants something original. Something no Uchiha uses. Something that's entirely his.
While impressed, he kept his expression neutral and asked calmly, "Have you thought about how your style will work? Do you have a direction yet?"
Aizen nodded, his demeanour shifting into something sharper, more focused.
"Actually… I do," he said, voice serious now. "In fact, I've already started working on it."
Kakashi blinked. This was new. He hadn't heard about this level of planning.
Aizen leaned forward slightly, his tone low and deliberate. "I'm planning to base my sword style on the patterns of natural elements."
"Patterns?" Kakashi repeated, confused.
Sakumo, on the other hand, waited patiently.
Aizen nodded. "From what I've observed, most lightning-style kenjutsu users use Lightning Release jutsu to boost speed and strike power, to overwhelm the enemy as quickly as possible. Is that right, Sakumo-san?"
Sakumo gave a small nod. "Yes. That's true. My own style follows that principle more often than not. Fast, decisive, lethal."
"Hmm," Aizen hummed thoughtfully. "And fire-style users, especially those in my clan, often combine fire jutsu with kenjutsu, using bursts of flame to pressure the opponent."
"Exactly," Sakumo agreed. "So what's different about your approach?"
Aizen's eyes sharpened. "My plan is to create a sword style that doesn't just use elemental jutsu. I want the style itself to follow the behaviour of those elements, before even adding chakra techniques."
"You mean…" Kakashi started, puzzled.
"A pure sword style," Sakumo muttered, eyes narrowing slightly.
He understood now what Aizen meant by "patterns."
Aizen nodded again. "Yes. I want to mimic the qualities of the elements, their natural rhythm, flow, intensity, within my swordsmanship itself. Not as an addition, but as a foundation. The jutsu will come later, but the core has to be elemental in spirit, not just in chakra."
That got Sakumo's full attention.
"Did someone give you this idea?" Sakumo asked, still finding it hard to believe such a refined thought came from a five-year-old.
Aizen shook his head. "No. I haven't talked to anyone about this. You're the first person to know."
Sakumo raised an eyebrow. "Why me? Why not share it with your own family?"
Aizen gave a small shrug, his tone casual but deliberate. "Well… isn't being a ninja about secrecy?"
That earned a small smirk from Sakumo, but Aizen wasn't done.
"I don't want others knowing too much about this yet. And besides," he said, looking up at the famous White Fang without hesitation, "you're a hero of the village. You believe in the Will of Fire. I figured… if there's anyone I can trust with this, it's you."
Sakumo was quiet for a moment, not out of doubt but out of genuine surprise.
This kid… he really meant every word.
And more importantly, he was thinking like a shinobi already.
"Well..." Kakashi started, but the words stalled halfway out of his mouth. He looked away awkwardly, unsure how to ask what he was thinking.
Aizen caught on immediately. He smiled gently, understanding the hesitation.
"Don't worry, Kakashi," he said calmly. "I don't plan to keep it a secret from you."
Kakashi blinked, a little surprised.
Aizen continued, his tone sincere. "If it weren't for you, I wouldn't have met Sakumo-san in the first place. And even though we're from different clans… in my eyes, we're all part of the same village. A village is just a big clan, right? With all its clans as family members."
He gave Kakashi a small grin. "So, even if we come from different roots, we're still the same. That's how I see it."
Sakumo nodded, clearly pleased by Aizen's words. There was a calm weight in his expression, the kind that came from years of fighting and living by the same ideals.
"You're right," he said with quiet conviction. "We've all gained the protection of this village, and in return, we have a duty to protect it, no matter which clan we come from."
He looked between the two boys, a faint smile crossing his face. "The Will of Fire… it lives in words like that."
Kakashi glanced at his father, then at Aizen.
"…Thanks," he said softly, almost awkwardly, "for letting me hear all that."
Aizen waved his hand like it was nothing. "It doesn't matter. It's not some big secret between us."
Then his gaze turned serious again as he looked back at the elder in the room.
"So yes… I want to create a pure sword style. One that's based on the natural behaviour of elements, not just using elemental jutsu to boost attacks."
Sakumo folded his arms, giving Aizen a long look. "You should know, a sword style on its own without jutsu can be limiting in real combat. Eventually, you'll need something that can adapt. Unless… you're much faster than your opponent."
"After all," he added, "most kenjutsu, at its core, is about speed. Getting in and ending the fight before the other person can cast."
Aizen nodded, already expecting that line of thought. "I know. I figured that part out early. That's why… I already have a plan for the speed."
"Hmmm…" Sakumo hummed, watching Aizen with a thoughtful look. "Would you like to see my kenjutsu in action?"
Aizen's eyes lit up like stars in the night sky. "Can I?!"
Sakumo couldn't help but chuckle inwardly. He really was just five years old, no matter how sharp his mind was.
"Yes," he nodded, then turned to his son. "Kakashi, bring my blade."
Without a word, Kakashi left the room and returned shortly after, carrying a sheathed sword with both hands. Aizen's eyes followed the blade with curiosity, expecting it to be a simple training weapon.
It's probably just a practice blade, he assumed.
"Let's go," Sakumo said, rising to his feet and heading toward the backyard.
Aizen and Kakashi followed closely behind, anticipation building in the air as they stepped into the open space behind the house.
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Suggestions for MC