Lin Yi casually set his in-game backstory as a Senju and Tsunade's younger brother, then unexpectedly transmigrated to the Hokage world, taking over Nawaki's identity and becoming Tsunade's only younger brother.
From the start, he had the Senju clan's top-tier bloodline and unlocked max-level Konoha-Style Taijutsu. The one thing he couldn't do was even the basic Three Basic Techniques, so after enrolling, he had no choice but to become Uchiha Mikoto's student, while also flirting with a whole crowd of familiar faces.
Just because he grew close to Mikoto, a clan beauty, Lin Yi was surrounded by Uchiha clan members. To everyone's surprise, he effortlessly crushed several provocateurs with nothing but basic taijutsu, stunning the entire crowd with his strength.
In Konoha during the Second Shinobi World War, with an overpowered ace up his sleeve and Tsunade at his back, Lin Yi began a cheat-fueled life of coasting to victory and dominating the ninja world on the strength of his Senju bloodline.
The plot is average, The immortal body is at full level and cannot exert its power.