Naruto: Borrowing from the Future

In Year 46 of the Hidden Leaf, on the eve of the Battle of Kannabi Bridge, Uchiha Aoya finally unlocks his cheat after two and a half years as expendable fodder on the front lines.

Good news: The system lets him learn ninjutsu, synthesize kekkei genkai, and even boost his innate talent!

Bad news: He has to spend chakra every day to repay his loans.

Good news: He can lend to other people, too!

By enhancing other people's talent, he can raise jonin to Kage level, Kage-level ninja to beyond Kage level, and those beyond Kage level to Six Paths level-all while earning handsome returns himself.

"But what if someone doesn't trust me and refuses my help?"

Then he'll just have to turn up the difficulty for the entire ninja world!

Help Orochimaru escape pursuit after his desperate defection. Help the Hidden Cloud avert a crisis that nearly destroys the village. Help the Akatsuki fight the Five Great Nations after being exposed ahead of schedule. Help Obito stay alive after his identity is revealed. Help Black Zetsu complete the Eye of the Moon Plan after his conspiracy comes to light...

Future Loan services are now online, dedicated to providing assistance to every ninja in dire straits.

Just don't ask who put them in those dire straits.

Years later, Uchiha Madara returns from the Pure Land. Faced with a ninja world where Kage-level fighters are worth less than dogs and beyond-Kage powerhouses are everywhere, he starts wondering whether he's been dead a little too long.

P.S. This story leans toward an overpowered protagonist.