In the world of "Eden," there are various species that used to interact with each other. However, differences in appearance and abilities caused them to look down on each other and engage in small conflicts. Humans and Elves, in particular, were often ridiculed together due to their similar appearances, and they became more aware of each other. Eventually, the Elven Kingdom, ruled by Elves and Dark Elves, declared war on the human country of "Gravefield." The protagonist, Grey, leader of a mercenary group, participates in the war against the Elves but is defeated in battle and taken prisoner. His treatment is cruel, being forced to perform harsh labor in the mines during the day and used as a tool for the elves' sexual release at night, leaving him physically and mentally broken. One day, Grey is involved in a mining accident and discovers the secret of Eden. With newfound power, Grey and his comrades begin a rebellion against the Elves.