Naruto

 Naruto Uzumaki is a young boy who has the Nine-Tailed Demon Fox sealed within him. Twelve years before the start of the series, the Nine-Tailed Demon Fox attacked the ninja village Konohagakure, slaughtering many people. In response, the leader of Konohagakure – the Fourth Hokage – sacrificed his life to seal the demon inside Naruto when he was a newborn. Konohagakure, however, regarded Naruto as if he were the demon fox itself and mistreated him throughout most of his childhood. A decree made by the Third Hokage forbade anyone mention the attack of the demon fox to anyone although Naruto soon realized about this. Years later, Naruto graduated from the Ninja Academy by using his Shadow Clone Technique, a technique from a forbidden scroll that he was tricked into stealing, to save his teacher, Iruka Umino, from the renegade ninja Mizuki. That encounter gave Naruto two insights: that he was the container of the demon fox.