TV Special
Description
A Marine officer stationed at Sabaody Archipelago, the Younger Marine Brother operates under the Benevolent King of the Waves. His duties include a critical mission to deliver an activation key for a security weapon targeting the Straw Hat Pirates' reunion.

He fought alongside his older brother as rank-and-file Marines during the Summit War of Marineford. Amidst the chaos of clashing Devil Fruit users, he faced near-catastrophe—trapped under debris and nearly crushed by Oars Jr.'s severed leg. Monkey D. Luffy's intervention inadvertently created an escape path for both brothers. This experience profoundly shapes his perspective, fostering open admiration for Luffy's determination to save Portgas D. Ace and cementing his own resolve to protect his brother.

He exhibits a lighthearted and occasionally irreverent demeanor. He frequently teases his older brother about his slower career progression, motivated by a desire to spur him on rather than malice. Unconventional opinions surface openly, such as jokingly declaring Luffy the "strongest" during a bar debate, much to his brother's disapproval. This humor extends to operations; he sometimes prioritizes socializing, lingering in bars to join patrons' arguments and earning reprimands.

His role in the Sabaody incident involves accidental complicity. He mistakes a young girl's fan letter for the delivery item, placing it in his bag while leaving the weapon's activation key in the envelope. This error triggers a chain of events where the girl pursues him to recover her letter. When Marines confront her, he intervenes, defending her youth and lack of malicious intent to argue for leniency. His intervention aids de-escalation after she discards the letter—briefly mistaken for the key—sabotaging the weapon deployment.

His character development emerges through interactions. The teasing of his brother masks deep respect, reflecting the vital familial loyalty proven at Marineford. Defending the girl and acknowledging Luffy's positive influence demonstrate a moral flexibility that prioritizes individual empathy over rigid Marine protocol.