Overview
Monkey D. Luffy (モンキー・D・ルフィ) is the protagonist and captain of the Straw Hat Crew in Eiichiro Oda’s One Piece. The licensed English edition from VIZ states the childhood aim plainly: become King of the Pirates after he gains rubber powers at the cost of swimming. The official One Piece character page likewise identifies him as captain, with the straw hat received from Red-Haired Shanks as his trademark.
The promise that starts the voyage
In Windmill Village he befriends Shanks, eats a Devil Fruit, and is saved from a Sea King at the cost of Shanks’s arm. The hat is left with a promise to become a great pirate and return it. That promise is why he leaves East Blue at 17 looking for the One Piece. He is also the son of Revolutionary leader Monkey D. Dragon, grandson of Marine Vice Admiral Monkey D. Garp, and sworn brother to Portgas D. Ace and Sabo. Those facts matter later in the story; they are not the reason he first sets sail.
What stays constant
He is usually cheerful and careless with details, then immovable when a crewmate’s dream or life is threatened. Gathering people who already have their own ambitions is how he pursues Pirate King, not a side activity. The first swordsman he recruits is Roronoa Zoro; the shipwright who later builds the crew’s current ship is Franky. The rest of the crew—Nami, Usopp, Sanji, Chopper, Robin, Brook, and Jimbei—join for their own reasons. Mentors and rivals such as Shanks and Blackbeard frame the era he sails through, but they do not replace that crew method.
Power stages, and what the names mean
Early chapters treat the fruit as the Gum-Gum Fruit: stretch attacks such as Gum-Gum Pistol, and a permanent inability to swim. The official character page now lists both that older name and a later classification—the Human-Human Fruit, Model: Nika, a Mythical Zoan. Older volumes and many franchise summaries still say Gum-Gum. This guide treats the later name as the story’s revealed classification, not as proof that every earlier chapter printed it on the page.
Gear 2, Gear 3, and Gear 4 are costly ways of using the same rubber body—speed, size, or Haki-coated striking power—not new Devil Fruits. Gear 5 belongs to the later reveal and should not be used as another nickname for every rubber attack. Armament, Observation, and Conqueror’s Haki appear as the voyage demands them. Seawater and Sea-Prism Stone still sap him, as with other Devil Fruit users.
His Marine bounty rises after major incidents. It measures how dangerous the government considers him, not who would win a fight. Story summaries later place him among the Four Emperors; treat that as a political label that can move with new chapters.
Creation and portrayals
Oda has said he chose the name because it felt right, and early design aims included a “manliness” reminiscent of Toriyama’s Dragon Ball. Mayumi Tanaka voices him in the Japanese anime. Colleen Clinkenbeard voices him in Funimation/Crunchyroll English releases. Iñaki Godoy portrays him in the live-action series, with Colton Osorio as young Luffy.