Naruto's Strongest Teacher

After experiencing the betrayal of the person he trusted most, he accidentally broke into a ninja world and became a glorious ninja teacher. "My name is Umino Iruka, and I will be the homeroom teacher of you brats from today on!" He was the first teacher of nine Konoha ninjas who made great names in the entire ninja world in just two years. He was also the most powerful ninja teacher in the history of the ninja world.