The narrative arc relies on the escalation of Cid's misunderstandings and their catastrophic impact on world powers:
- Season 1: Following his death on Earth while seeking magic, Minoru reincarnates as Cid Kagenou. He cures Alpha of demonic possession—which is revealed to be unstable magical overload from hero lineage—and fabricates the Cult of Diablos lore. Shadow Garden expands into an elite force operating behind the luxury brand Mitsugoshi. Cid inadvertently rescues Princess Alexia, eliminates Cult leaders Zenon and Lutheran, dismantles the Holy Sanctuary, and crushes royal champions at the Bushin Festival.
- Season 2: Cid intervenes in the Lawless City to defeat the vampire progenitor Elisabeth using Recovery Atomic, and later assumes the persona of John Smith to engineer a banking run. In the climax, Cid disrupts the royal wedding orchestrated by Doem Ketsuhat, obliterates the realm creature Ragnarok, and defeats Mordred. The battle triggers the Black Rose interdimensional rift, pulling Cid back into the demon-ravaged ruins of modern Tokyo alongside Akane Nishino.