Nami

"Cat Burglar" Nami is the navigator of the Straw Hat Pirates. She is the third member of the crew and the second to join, doing so during the Orange Town Arc. She is the adoptive sister of Nojiko after the two were orphaned and taken in by Bell-mère. She was formerly a member of the Arlong Pirates and initially joined the Straw Hats so that she could rob them in order to buy back her village from Arlong. However, she legitimately joined the Straw Hats after they rebelled against and defeated Arlong. Her dream is to make a map of the entire world.