Arios manifests as a mysterious figure within the frozen palace of the Seijū cosmos, a nascent universe gripped by crisis. Intrinsically bound to Queen Angélique Collette, Seijū's dormant ruler, he embodies her shadow manifestation. His existence stems from her unconscious state, directly tied to her inability to sustain the universe's equilibrium.

The Sacrea Spirit, an entity obstructing Queen Collette's awakening, designates Arios as pivotal to its scheme. Amidst the climactic confrontation, the spirit voices its intent to "separate" protagonist Ange while confronting Arios, cementing his role in the conflict. After the Sacrea Spirit's defeat through collective action, Queen Collette vanishes. As the dimensional corridor between universes collapses, Arios's fate remains unresolved, leaving Ange stranded in the Seijū Holy Land.