Buggy the Clown, also known by his later epithet "Buggy the Star Clown," is a pirate from the Grand Line who serves as the captain of the Buggy Pirates and, following the events of the Wano Country arc, is recognized as one of the Four Emperors ruling the New World. His most distinguishing physical features are his blue hair, his colorful, clown-like attire, and most notably, a large, round red nose that is his genuine feature and a source of extreme personal sensitivity. He becomes enraged when anyone mentions or makes fun of his nose, often lashing out violently against the offender.

Buggy's background is deeply rooted in the legendary era of piracy. As a child, he was an apprentice on the ship of the Pirate King, Gol D. Roger, serving alongside his comrade and friendly rival, Shanks. During their time on the Oro Jackson, Buggy and Shanks were known for their constant, trivial arguments. On one fateful occasion, Buggy acquired a treasure map and planned to secretly sell a Devil Fruit the crew had obtained to fund his own treasure-hunting crew. When Shanks unexpectedly startled him, Buggy hid the fruit in his mouth and accidentally swallowed it, gaining its powers but losing the ability to swim and also losing the treasure map into the sea. He has held a bitter grudge against Shanks for this incident ever since, blaming him for ruining his plans. He was present at his captain's execution in Loguetown, where he wept openly, and after Roger's death, he rejected Shanks's offer to join his crew, choosing to form his own pirate band.

In terms of personality, Buggy is theatrical, arrogant, and deeply selfish. His speech is frequently peppered with the word "flashy," reflecting his desire for grandiose and attention-grabbing actions. He believes a pirate's true nature is to plunder treasure and initially showed little regard for his subordinates, once using his own crew members as human shields to protect himself. Despite his bluster, he is acutely aware of the dangers of the Grand Line and is prone to cowardice, often seeking to flee from powerful opponents. However, he is also incredibly opportunistic and possesses a remarkable degree of dumb luck. This luck, combined with his talent for deception and theatricality, often leads others to misinterpret his cowardly actions as signs of great leadership and strength, allowing him to gain followers and fame far exceeding his actual combat prowess.

Buggy's primary motivation has always been the accumulation of treasure, with his ultimate dream being to become the Pirate King. This goal is driven by a purely materialistic view of piracy, in stark contrast to many of his contemporaries. He is also motivated by revenge, first against Luffy for his defeat in Orange Town and later against Shanks for their past grievances. After the Marineford Summit War, he becomes more focused on leveraging his reputation and influence to create a powerful organization.

His role in the story evolves dramatically. He begins as a minor antagonist in Orange Town, where he is defeated by Monkey D. Luffy. He later becomes an unlikely ally of circumstance during the Impel Down prison break, where he inadvertently leads a massive riot. This event, combined with his former connection to Roger, leads to him being hailed as a hero by a group of dangerous criminals. During the Marineford War, he is thrust into the spotlight, and his public association with other major powers leads the World Government to mistakenly believe he commands a formidable force. As a result, he is invited to become a member of the Seven Warlords of the Sea. He uses this position to found a mercenary organization called "Buggy's Delivery." After the Warlord system is abolished, he becomes a primary target of the Marines. In a final twist of fate, he joins forces with Crocodile and Dracule Mihawk to form the "Cross Guild," where the public mistakenly identifies him as the leader. This misconception, coupled with the defeat of two other Emperors, catapults him to the position of a Yonko, or one of the Four Emperors.

Key relationships define much of his journey. His most significant relationship is with Shanks, a man he claims to hate but with whom he shares a deep, complex history as brothers-in-arms. He also has a unique relationship with Monkey D. Luffy. While he seeks revenge on Luffy for their initial encounter, Luffy is also the inadvertent cause of his rise to fame, and Buggy is one of the few people who knows that Luffy's success is not based on the luck that carries Buggy himself. He formed an odd friendship with Portgas D. Ace, who once crashed one of his crew's parties. His alliance with Alvida has been one of his most stable partnerships, and his crew members, Mohji and Cabaji, remain blindly loyal to him despite witnessing his weaknesses.

Regarding his development, Buggy transforms from a petty, small-time tyrant in East Blue into a major political player in the New World. He does not grow significantly in strength or moral character; rather, his development is a satirical rise to power built entirely on a foundation of misunderstandings, reputation, and his own talent for riding the wave of chaos. He has learned to weaponize his fame, becoming a master of projecting an image of power that he does not truly possess.

Buggy's notable abilities are derived from the Bara Bara no Mi, a Paramecia-type Devil Fruit that allows him to split his body into many pieces. He can control these detached parts, making them fly through the air to attack from a distance. This ability grants him complete immunity to slashing attacks, as swords and blades will simply cut his body into pieces without causing him injury. However, the ability has limitations; his feet must remain on the ground to control the floating parts, and his body parts have a limited range of control. His primary weakness is blunt force trauma, which can still injure him. In combat, Buggy uses his powers to perform deceptive maneuvers, often holding knives between his fingers to attack opponents from unexpected angles. He is also an inventor of powerful explosives, most notably the "Buggy Ball," a highly destructive cannonball, and its miniature version, the "Muggy Ball". Despite these tools and his unique immunity, his overall combat strength is relatively low compared to the powerful pirates of the New World, and he relies almost entirely on his charisma, luck, and reputation to survive.