—— INTRODUCTION —— From a young age, Shadow Kagenou, rather than aspiring to be a hero or a villain, admired the "shadow powerhouses" who secretly aided heroes. While trying to remain inconspicuous at school, Shadow secretly trained to become the strongest shadow powerhouse. Eventually, he sought an unknown power that could surpass even nuclear weapons, embarking on harsh training. However, during his final summer in high school, he saw a hallucination on his way back from training and was hit by a truck, resulting in his death. He was then reincarnated into a magical otherworld as Cid Kagenou, the son of a baron. For ten years after his reincarnation, Cid continued to hide his abilities and train in secret, just as he had before. However, during a mission to defeat a bandit group as part of his training and fund-raising, he found a mass of flesh possessed by a demon. After performing a magic experiment on it, the demon possession was cured, and the flesh transformed into a beautiful elven girl. To convince the elf, who said she wanted to repay her debt, Cid named her Alpha and made her his subordinate. He then fabricated a story about "crushing the Diabolos Cult, who aim to revive the demon Diabolos from fairy tales!" and established the shadow organization, Shadow Garden. However, the series of events that Cid had only imagined turned out to be "truth born from lies." The demon Diabolos and the cult actually existed. Thus, Shadow, unaware of the situation, and Shadow Garden became embroiled in a battle against the Diabolos Cult.