Sakazuki, formerly alias Akainu, serves as a supporting antagonist in the story. As the Marines’ Fleet Admiral, he swiftly mobilizes naval forces to counter Byrnndi World, an Impel Down escapee endangering the World Government. When alerted to World’s submarine base, Sakazuki authorizes a Buster Call to annihilate the site, showcasing his unwavering commitment to Absolute Justice through ruthlessly efficient methods—even at the cost of collateral damage or endangering allies such as Buggy the Clown.

His philosophy rejects compromise, favoring overwhelming force over diplomacy. During the assault, he mirrors past extremes, like sinking civilian vessels during the Ohara Buster Call to purge scholars, prioritizing total eradication of threats above all else.

Physically imposing, he bears facial scars from his duel with Admiral Kuzan. Post-timeskip, he dons a white Fleet Admiral uniform, retains his Marine cap, and grows a mustache and goatee. His stern demeanor tolerates neither failure nor dissent among subordinates.

The narrative emphasizes his strategic enforcement of Marine authority rather than personal backstory. His role culminates in the submarine base’s destruction, cementing his legacy as the World Government’s relentless enforcer.