An Unconventional Kamen Rider: Regeido Protects All Worlds

An ordinary young man, whose name happened to be the same as Kamen Rider Rejendo, broke down after losing his loved ones. After taking his own life, he transmigrated into a parallel world as Kaguya, Kamen Rider Rejendo. Then his butler transformed into a System and told him that every world was facing a crisis and needed his help. Thus began his journey to save the myriad worlds.