Sebastian, a Wotan born of fish-man and giant heritage, sails as a World Pirate. His origins before the crew remain shrouded, but his loyalty emerged in countless clashes against navy warships and competing pirates. He endured the crew’s violent mutiny when Byrnndi World, their captain, fell to Byojack’s treachery. Fleeing with survivors, Sebastian later helped reclaim their captain using a salvaged vessel they called their “dream ship.”

In a skirmish against Monkey D. Luffy and Boa Hancock, Sebastian taunted his foes, boasting victory within two minutes. His blindness shielded him from Hancock’s petrifying allure, yet Luffy’s Gum-Gum Gigant Pistol shattered his defenses. Perona’s despair-inducing powers finally subdued him. After the battle, Admiral Sakazuki’s forces annihilated the World Pirates’ ship, leaving Sebastian’s fate lost to the sea.

A master of environmental camouflage, Sebastian fought with twin maces, blending Striker ferocity with Powerhouse resilience. His combat tactics centered on mitigating damage through strategic positioning and manipulating battlefield conditions to his advantage.