1 Kizaru

In one of the bookstores in Konoha, there is a 12-year-old boy immersed in his reading. Despite his age, he stands tall, appearing as if he were 15 or 16 years old. Wearing yellow-tinted sunglasses, he sits comfortably, enjoying his tea in peace.

Slam! The sliding door suddenly makes a loud noise.

"Kizaru! You're being lazy again! Didn't I tell you to look after the store?" scolds an old man's voice.

"I am looking after the store," Kizaru calmly responds, keeping his eyes fixed on Kakashi's favorite book.

"You're not allowed to read that! I told you to look after the store! Instead of being lazy, at least clean the dust off the bookshelves or sweep the place!" admonishes a middle-aged man dressed in a white Japanese robe.

"Hai, hai," Kizaru helplessly answers as the store owner takes the book, leaving him feeling a bit bored once again.

"This child..." the owner mutters, looking at Kizaru's face. He wants to teach Kizaru a lesson but decides against it.

Kizaru's parents were ninjas, and the bookstore owner was once saved by Kizaru's father during a nine-tailed incident twelve years ago. Although the ninja saved him, Kizaru's father did not survive. Kizaru's mother passed away while giving birth to him, leaving no one to care for him. As a result, the bookstore owner had no choice but to adopt Kizaru in order to repay the favor.

However, over time, while raising Kizaru, the owner noticed that he was different. This child, Kizaru, could be carefree at times and serious at others, often displaying cowardice. Kizaru had the opportunity to enter the ninja academy a long time ago, but at the age of 6, he simply declined. Akihara, the bookstore owner, remembered Kizaru's response that day: "Becoming a ninja? It's too troublesome and dangerous... I want to live much longer."

Akihara didn't know whether to laugh or cry at that time. Contrary to his parents' bravery, Kizaru seemed to be timid and carefree.

...

While cleaning the store, Kizaru appears lost in thought.

He has been in this world for 12 years now and, as someone who came from Earth, he knows that he is in the Naruto world with the power of one of the admirals from One Piece, Kizaru.

Since arriving in this world, he has deliberately avoided getting involved with many of the well-known characters except for Kakashi, choosing to grow silently and even refusing to enter the ninja academy because of it.

Although he doesn't know much about the plot of Naruto, he is familiar with Kizaru from One Piece since he watched it for nearly 800 episodes before stopping. He knows that Kizaru consumed the Glint-Glint Fruit, mastered six form style and also developed proficiency in Armament Haki and Observation Haki.

And as for how he was able to grow stronger and more powerful, Kizaru discovered that by acting relaxed and complacent like the original Kizaru, he was able to make significant progress.

Although this method of becoming powerful seemed easy, Kizaru knew that it only increased his proficiency in Haki and mastery of his Devil Fruit to a certain extent. He still needed to train like ordinary people.

In secret, when ordered by the owner to buy groceries or during his outings, he dedicated two years to mastering the Marine's Six-Form Style techniques.

And what about Haki? That also required practice to improve his proficiency.

Although Kizaru didn't have a system to make his life completely easy, he believed it was for the best. It taught him to be more vigilant and never underestimate this world.

Through his training, Kizaru considered the possibility that, even though he inherited Kizaru's powers and knowledge of techniques, he was not limited to the original Kizaru's full potential. He might even surpass the original Kizaru, as he felt he had untapped potential and benefited from the new power system in this world.

Kizaru's biological parents were ninjas, and the bookstore owner didn't keep everything hidden from him. He even handed down the possessions left by Kizaru's parents: 1.2 million ryo, knowledge of Chakra, ninjutsu, shuriken, and kunai.

Despite not entering the ninja academy, Kizaru developed his chakra and trained to become a ninja. He learned how to control his chakra, allowing him to stick to trees and walk on water.

Kizaru realized that his physical abilities alone were already at the level of a top-tier Jonin.

In terms of his chakra capacity and level, he had also reached the peak level of a Jonin. This was mainly due to Kizaru's exceptional talent and his body being on a different level compared to the people of this world. As a native of the One Piece world, he had an obvious advantage in terms of physical abilities. He had trained his body to this point at a young age, and his One Piece native cells contributed to his large chakra pool, further enhancing his power. With the wind and fire attributes inherited from his parents, Kizaru would have no problem surviving even without the abilities granted by his Devil Fruit.