When he was in Konoha, he started out as Tsunade's childhood sweetheart. This start required him to change his fate.

The tragedies of World War II and World War III, and the decline of Konoha, all disappeared.

I want to hold Tsunade's hand and walk step by step to the top of the ninja world.

Uchiha Madara, Otsutsuki Kaguya, come if you can!

Bad News: Waking up in a different world. Good News: It's Prince of Tennis. Bad News: The protagonist was a tennis novice before the time travel. Good News: He met Jujiro, a demon who hadn't yet joined the U17 team. Furthermore, he awakened the mysterious Six Paths Dimension, where opponents he'd previously played against can appear in his dreams. Furthermore, each door in the Six Paths Dimension grants him a special ability bonus. After witnessing the rise of demons and facing off against the young "First Army," the protagonist joins Seigaku, completely overhauls the tennis club, and leads it to the national championship. He lays low in the U17 team, hones his skills in the expedition team, and rises to fame in the World Cup. Ultimately, he becomes the tennis king everyone dreams of! The synopsis is too much to read, but after the transition period, the excitement begins with the Jr. Tournament section. (Already available: the excellent Prince of Tennis fanfiction "In Prince of Tennis, I Have a Tennis Mini-Game...")

Beichen Xi, a boy shrouded in mystery, hails from the mythical and legendary land of Huaxia. He's widely hailed as the most likely candidate to win the world's junior tennis championship. He loves tennis, yet he's never seriously challenged his opponents. He loves competition, yet he never lets his opponents score a single point. He loves a challenge, yet he exploits his opponents' strengths. －－－－－－－－－...[A little confusing]