Naruto: By lying low and hiding, he eventually became the leader of the Legendary Sannin.

Original title: Naruto: By Hiding and Hiding, He Became the Leader of the Three Legendary Sannin Alternative title: Naruto: Tsunade's Wife Should Have Been Raised from a Young Age
Tags: Anime derivative, Time travel, System, Anime, Naruto, Invincible, Fan fiction, Soul travel
Main character: Uchiha Kagura
Synopsis: System + Invincible protagonist + Decisive ruthlessness + High intelligence. No saintly figures, please read with confidence.
Reincarnated, he became a member of the Uchiha clan. He punched Orochimaru and kicked Jiraiya. He also occasionally teased the underdeveloped Tsunade.
Since you've decided to marry Tsunade, you should start training her from a young age!
It's a tablet now? Don't panic, my wife knows all too well what her future holds.
Who can understand the joy of nurturing children from a young age?
With his own instruction manual and system, he became the strongest of his generation.
What Rinnegan? What Sage Mode? What Forbidden Techniques? Aren't these things given out for free by the system?
What?! Kaguya Otsutsuki has been resurrected?! Why are you all looking at me like that?! Naruto, Sasuke! Where the hell are you?!
Because of his exceptional strength, he was regarded as the leader by the three legendary ninjas. Unbeknownst to him, he became the legendary child of prophecy and stood before the final boss.
Note: This book only covers the storyline of Shippuden.