Accidentally traveling to the world of the comic version of Prince of Tennis caused a change in the world line.

The champion Rikkai University completed an unprecedented three consecutive national championships.

Kunimitsu Tezuka did not let injury ruin his three-year tennis career.

Echizen Ryoma has completely turned evil, and he firmly believes in staying in the American team and waiting for an opportunity to avenge Byodoin Phoenix.

...

The person who triggered this butterfly effect was a Quincy who escaped the large-scale [Sacred] punishment when Yhwach awakened and fled here.

Mu Yue traveled to the world of Naruto and became an ordinary chuunin teacher at Konoha Ninja School and a member of the Root Organization.

Fortunately, after awakening the teacher system, you can become stronger by teaching.

In order not to become Danzo's consumables, Mu Yue worked hard to teach and increase her strength.

"Complete the teaching rated A for the first time and receive the reward - mastery of fire attribute chakra properties change."

"Under your guidance, this disciple has worked hard to practice, and his overall strength has been greatly improved, and he has been rewarded - the Immortal Human Body!"

From then on, there was a teacher in the ninja world who only wanted to make his students strong.

Shisui was not blinded by Danzo, and he successfully prevented Uchiha from annihilation.

When Metkai met the Seven Ninja Swordsmen, he no longer watched helplessly as Metkai opened the door to death and fought hard.

Obito defeated Uchiha Madara's conspiracy and did not turn into a psychopath. He was still the enthusiastic young man who was eager to help others and wanted to become Hokage.

(ps: There is a high-quality old book on Naruto with 21.78 million words, quality guaranteed)