Shion, younger sister of Meeyon, begins as a member of the antagonist’s quartet, tasked with infiltrating the protagonists’ ranks undercover while masquerading as an ally. Her combat prowess centers on a sitar modified to function as a cello-like weapon. Following a fatal encounter with the Destruction Virus, Sanzo’s harmonica—empowered by six recovered keys—resurrects her, unlocking its latent healing properties.

Reborn, Shion gains transformative abilities, shifting into a blue-haired humanoid form reminiscent of her sister to adapt to shifting circumstances without severing ties to her companions. A shape-shifting parrot accompanies her on missions, transforming into a functional walkie-talkie to enable covert coordination.

Her loyalties evolve from covert sabotage to authentic allegiance with the heroes. She plays decisive roles in confrontations against their central foe, deciphering critical vulnerabilities in enemy tactics. This arc concludes as she joins their temporal expedition, intertwining her destiny with their pursuit of ancient relics and ultimate reconciliation.