At Night.
Four-year-old Katsumi Kei sat cross-legged, quietly reading the book Chakra Refining Technique, his eyes calm and focused. He memorized, absorbed, and analyzed every line.
Kei had been in the Naruto world for four years.
At just six months old, he lost both parents in the Nine Tails Rebellion.
Thus, he became an orphan.
Thankfully, his parents were both ninjas who died defending the village, so Konoha treated him well. A caretaker was arranged during his infancy, he received an orphan's pension, and his parents' inheritance was passed to him without a single ryo missing.
His mother, Inuzuka Hanabe, was a ninja of the Inuzuka Clan. His father, Katsumi Kato, was a rare civilian Jōnin.
Because of them, Kei inherited more than just money and a house. He also received a ninja's legacy.
Among his inheritance:
The Inuzuka Clan's Chakra Refining Technique
Three Body Technique
Ninja Tool Throwing Technique
Body Flicker Technique
Shadow Clone Technique
Konoha Fluid Technique
A series of Wind Style jutsu, including: Breakthrough, Great Breakthrough, Beast Wave Palm, Gale Palm, Beast Wave Gale Palm, Vacuum Sphere, Big Vacuum Sphere, Continuous Vacuum Sphere
It was clear: Katsumi Kato had been a Jōnin well-versed in Wind Style.
Most of these jutsu were fairly common, but one inheritance stood out: the Inuzuka Clan's basic Ninja Dog Training Manual—and the ninja dog himself, Hayate.
Even if it lacked secret clan techniques, Kei was deeply satisfied. He and Hayate had been together since birth. While four years old would be middle-aged for a normal dog, for an Inuzuka-trained ninja dog, Hayate was still considered a pup.
He was handsome, pure white like a snow-sheepdog hybrid, and already possessed notable combat ability. A true battle-type companion.
Kei now leaned against Hayate's fluffy body, silently reading.
The Inuzuka chakra refining method wasn't as famous as the Hyūga's, but it far outclassed the basic academy version.
Chakra, the source of all ninja power, was formed by extracting physical energy from every cell in the body—130 trillion in total—and merging it with spiritual energy accumulated through experience.
It sounded simple. But how to extract, how to merge, and how to circulate safely—these were everything.
Poor chakra refining could damage the body or mind. Clans like the Inuzuka had refined their methods over generations to avoid such risks.
Over the last four years, Kei had been learning the world's language, absorbing knowledge, and training his body consistently.
He didn't overtrain. He didn't skip days. He simply persevered.
And now, at four years old, Katsumi Kei possessed the physique of a fully-grown adult male from Earth.
Most children began chakra refinement at age six.
But tonight, Kei would begin early.
After rereading the technique a final time and confirming he fully understood it, he closed his eyes.
He focused.
He drew physical energy from his cells.
He drew spiritual energy from his mind.
He guided both into convergence.
A reaction occurred.
In less than three minutes, his first strand of chakra was born.
And then—
[Ding!]
[Host has mastered special energy: Chakra]
[Divine Pet System has been activated]
[Summoning Beast Evolution Function has been unlocked]
[Opening...]
[Host: Katsumi Kei]
[Summoning Beast(s): None]
[Talent: Intelligence]
A translucent panel hovered in front of his eyes.
Kei's expression flickered with excitement.
'I had talent, but now I have this system too? Even better.'
He quickly opened a drawer and pulled out a summoning scroll. Hayate had always been his partner, but they hadn't officially signed a contract. Without chakra, Kei hadn't been able to.
Now, he could.
And more importantly, he should. He needed to understand the system's evolution function.
"Hayate, once we sign the summoning contract, you'll officially be my summoning beast. I look forward to our journey together."
Hayate's ears perked. His fluffy tail wagged vigorously. His big, intelligent eyes glowed with excitement.
"Woof!"
Kei smiled. He understood perfectly.
Hayate had been waiting for this.
Without hesitation, Kei bit his thumb and pressed his bloodied finger to the scroll, infusing the small amount of chakra he'd refined.
The scroll responded immediately, glowing faintly as a strange link formed between them.
[Ding!]
[Host has obtained a Summoning Beast: Ninja Dog Hayate]
[Opening the Summoning Beast Attribute Page]
[Opening...]
.....
Please note:
Kei is the MC's given name.
Katsumi is the surname.