"Vaan (ヴァン Van) is a 17 year-old orphaned Hume street urchin who lost his parents in a plague when he was 12 years old. His only brother, Reks, died two years prior to the start of the game, during the Archadian invasion of Dalmasca. He makes a living as Migelo's assistant, running various errands for him, while at the same time pickpocketing from Archadian soldiers while claiming to take back what is Dalmasca's. He is a cheerful and energetic boy. Vaan dreams of someday becoming a sky pirate in command of his own airship. He trains to meet this goal by killing dire rats in the sewers of Rabanastre on a daily basis, for which Dalan gave him the nickname "Vaan Ratsbane." Despite nominally being the main protagonist (as the player starts the game controlling him), the majority of the game focuses on the events and conflicts of the world as a whole and of Ashe, rather than Vaan's individual problems, with his character instead used as a narrative device to allow the player to follow the events as an outside observer."
Source: Wikipedia, "Characters_of_Final_Fantasy_XII", available under the CC-BY-SA License.