He was a friend of the Fourth Hokage, Minato Namikaze, and a student of the Sannin Jiraiya. Yet he became a Konoha rogue ninja simply because he grew too powerful. The Third Hokage was protecting him, too, because so many geniuses had died in Konoha.
After defecting, he was gravely injured and rescued by the Akatsuki. He eventually joined them, and that is where the story begins.
This novel and its characters are entirely fictional. Any resemblance to actual people or events is purely coincidental. Do not imitate.