Monkey D. Luffy, also known as "Straw Hat Luffy" and commonly as "Straw Hat",[10] is the founder and captain of the increasingly infamous and powerful Straw Hat Pirates, as well as the most powerful of its top fighters.[26][27] He desires to find the legendary treasure left behind by the late Gol D. Roger and thereby become the Pirate King,[28] which would help facilitate an unknown dream of his that he has told only to Shanks, his brothers, and crew.[29][30] He believes that being the Pirate King means having the most freedom in the world.[31] 

Born in Foosha Village, Luffy is the son of Monkey D. Dragon, the leader of the Revolutionary Army,[32] and the grandson of the Marine hero Monkey D. Garp,[33] and their family carries the initial and Will of D. At age 7, Luffy accidentally ate the Gomu Gomu no Mi, which turned his body into rubber.[34] Shanks also gave Luffy the very straw hat that has become Luffy's signature accessory, having gifted it to the boy as part of a promise for them to meet again someday after he became a great pirate.[35] Growing up on Dawn Island under the care of Curly Dadan,[36] Luffy befriended and became sworn brothers of the late "Fire Fist" Portgas D. Ace[37] and Revolutionary Chief-of-Staff Sabo.[38] 

Two years after the war, with his bounty increased to 400,000,000, he entered the New World and began challenging the Emperors and their allies directly, with his bounty going up to 500,000,000 after the Dressrosa Arc, and later all the way to 1,500,000,000 after the global revelation that he is Sabo's brother and the existence of Straw Hat Grand Fleet becoming public, as well as the events of the Whole Cake Island Arc. After leading the Raid on Onigashima and defeating Kaidou as well he became a member of the Four Emperors, his bounty was increased to 3,000,000,000.