Ramsus is the brother of Wilbert, the former Demon Lord, making him the maternal uncle of the series' central heroine Mio Naruse. As a demon, he leads the Moderate Faction in the demon world, opposing the aggressive policies of the current Demon Lord's faction and the radical elements within the Demon Council.

He first appears during the second season, specifically in *BURST*, emerging as a key political and military figure. Ramsus participates directly in the demon realm's tournament arc, initially aligning with forces challenging Basara Tojo and his allies. In combat, he wields considerable gravity-based magic.

Though initially an antagonist due to his faction's goals and actions against the main group, his motivations center on safeguarding the demon realm's stability and protecting Mio. When Chaos—a destructive entity awakened by radical forces—emerges, Ramsus shifts allegiance pragmatically, cooperating with Basara, Mio, and current Demon Lord Leohart to confront this greater threat.

Following the climactic battle against Chaos and the Demon Council's elimination, Ramsus's actions help reduce tensions and open a potential path toward peace among demon world factions. His involvement stems from his leadership role and familial bond with Mio, though his ultimate fate beyond *BURST*'s resolution remains undocumented.