The Naruto and Sasuke Training Diary

This book is also known as

"The Supporting Character Big Shot's Self-Cultivation"

"I'm Just a Background Character"

"My Golden Finger Can't Possibly Be This OP"

"Do You Like a Protagonist Who Doesn't Appear for Several Chapters in a Row, and Only Says a Few Lines When He Does?"

Behind every successful man, there must be another successful man.

And the protagonist... is the third man standing behind those two.

Naruto. The story is told mainly from Sasuke and Naruto's perspectives. Not BL; the title is purely clickbait ().