Nero found his Devil Fruit when he was 5 years old, inside of an anbondon Pirate Ship, he then ate it. As a child, Nero aspired to be a Pirate and met Edward Newgate. Being inspired by the captain, he told him about his dream. Wanting to become King of the Pirates. Whitebeard bet him that he couldn't do it and he told Whitebeard that he would, even if it meant kicking his ass. Because of his actions of escaping Impel Down, participating in the War of the Best, escaping from Marineford, and sneaking back into Marineford, that brought Nero's bounty up to 400,000,000.