Before transitioning to the 22nd century, a small country Nivalon, secluded, and yet more human and nature friendly, from the AI-dominated world, holds a nationwide fighting tournament for the purpose of constructing the foundation for their own safety. With guilt over his dad's death, Kai has since trained himself to be professionally skilled at Taekwondo. Now, the opportunity he could prove himself to be a physically and mentally reliable man is given in the tournament. His critical journey, ultimately leading him to be free from the deep-rooted guilt, starts with the other competitors at the hub of the nation.