I'm The Devil - Chapter 18: Birth of Zeus

Nagasawa crossed to Naruto Universe and was bound to Konohagakure.If Konoha is severely damaged and destroyed, Nagasawa’s lifespan will be reduced.He panicked at the thought of the upcoming Nine-Tailed Demon Fox's attack , and the thought of Konoha getting destroyed left him in despair.Fortunately, while bound to Konoha, he can obtain templates of powerful characters.At the beginning, He got the Whitebeard template! Since it's the Whitebeard from the Summit War of Marineford, he can use Tremor-Tremor Fruit's ability and Haki.Facing the Tailed Beast Ball, which terrorized Konoha Shinobi, Nagasawa leaped and shattered the Tailed Beast Ball with one punch!

An ordinary student accidentally traveled into an other universe and became the king of a small kingdom. He had gotten a “Cheating Code” of life and was able to complete something extraordinary. This is the story about a king that was able to conquer continents and leave behind him an ultimate legend that will be recited between every generation to come.

- Description from novelupdates

In a world where power defines worth and survival is a privilege earned through strength, Ronan was just another broken soul—bullied, beaten, and forgotten.Until he snapped.[System Activated][You have acquired an S-Class Ability: Starflame][Extreme rage and deep-seated hatred detected][You have obtained the unique skill: Devil’s Covenant]Once a victim, Ronan begins to rise—with a system by his side that grants him power through every action.When he cooks:[Skill Acquired: Home Cook]When he reads:[Skill Acquired: Speed Reading]When he fights:[Skill Acquired: Vital Strike]And these skills?They evolve.[Skill Devil's Covenant has upgraded into Devil's Divine Judgement][Skill Speed Reading has upgraded into Hyper Comprehension][Skill Energy Slash has upgraded into Demonic Slash]Every moment, every breath, every choice brings him closer to power.A hero, or a villain?He stands among them.

In this life, I will live for you.