Rukimedes I, the Original Demon King, endured millennia sealed within the Dimensional Rift after a cataclysmic rampage. Initially a devoted researcher and family man, he raised two children, Lake and Shion, while passionately pursuing magical studies, balancing intense focus with familial care. Tragedy shattered this life when Lake, aged three or four, and his mother perished in a landslide. Consumed by grief, Rukimedes plunged into obsessive magical research. His despair culminated in the creation of magic itself, a breakthrough that spiraled into madness. Unleashing destruction upon the human world, he faced the legendary hero Creasion and warrior Ross, who sealed him away—an act that erased magic until its eventual recreation centuries later.

An alternate timeline emerged through demon Elf November's interference. Here, Rukimedes discovered Mana—magic’s fundamental energy—earlier, aided by cryptic hints from Elf’s book. Elf also covertly placed a time-travel device in Rukimedes' possession. Unaware of its function, Rukimedes brought it home, where young Lake accidentally activated it. The malfunction hurled Lake and his mother forward in time, appearing to disintegrate before Rukimedes' eyes. Mistaking their disappearance for violent death by the machine, he suffered total mental collapse. This breakdown fueled his magical mania, accelerating his transformation into the Demon King and the rampage that led to his sealing.