Shion Adel Viccolobute is a high-ranking government minister in the secluded European city-state of Shahalta. He masterminds a political coup during the nation's transition from monarchy to republic, exiling the royal family members Princess Yutika and her infant sister Rasha to seize control. His driving motivation is acquiring Shahalta's legendary royal treasures, which he believes hold significant power or value.

To achieve this, Shion initially collaborates with subordinate Kochel van Stenwald, but later betrays and eliminates Kochel to assume direct command. He employs Viler, a hypnotic enforcer, to brainwash members of the Shahaltan Royal Guard into serving his regime, forcing them to act against their loyalties under hypnotic control.

Shion's forces clash repeatedly with Lupin III's group and the sky pirate rebels led by Yutika. His pursuit culminates in a confrontation aboard a flying treasure vault where he intends to secure the royal artifacts. During a physical struggle with Lupin, Shion nearly falls to his death but is rescued by Inspector Zenigata to face arrest. The treasures he sought prove less valuable than anticipated; Lupin reveals his true target was a simple gold corkscrew previously swallowed by an infant named Ramu. This outcome underscores Shion's miscalculation regarding the treasure's worth.

His actions exemplify political ambition and ruthlessness, utilizing manipulation and force to consolidate power. His downfall arises from his obsession with the royal treasures and underestimation of both his adversaries and the true nature of the artifacts.