"Fizz Possessed" describes Shibas Scotch's consciousness inhabiting Gin Fizz's body. This occurs after his crystalline form, achieved through his Super Mode transformation into a giant crystal-armored figure with angelic wings, shatters in combat. His vulnerable state leads to fragmentation, forcing his spirit to transfer into Gin Fizz's pure and compatible form. The two consciousnesses involuntarily share the same body, alternating control over actions and speech. Shibas retains his cynical, self-serving demeanor while dominating, creating tension. Gin Fizz maintains her own awareness, occasionally influencing actions to advocate for morality or express dismay at his behavior. Shibas uses her body to pursue personal gains like gambling or evading debts, dismissing her idealism.

Restoring Shibas requires his Soul Crystal, a MacGuffin essential for reconstructing his original form. If stolen or inaccessible, he remains trapped indefinitely. This possession recurs throughout the series. Their dynamic persists: Gin Fizz believes in Shibas's latent goodness despite his actions, while he openly mocks her optimism. Antagonists, such as Count Cuttlefish, exploit this possessed state for rituals, notably attempting to sacrifice Gin Fizz's virginal body to revive an ancient entity.