When the mysterious Cubes descended from the skies, humans gained access to magic, with each person’s rank determining their innate strength—and their worth. For Kai Amachi, a lowly Unranker with almost no magical power, life at the bottom means enduring the grunt work of dungeon expeditions for an uncaring party. But with his younger sister, Nagi, relying on him to cover her medical bills, giving up is not an option. Then disaster strikes when Kai is expelled from his party just as Nagi’s condition suddenly worsens. Unless he can pay the enormous hospital fee that is quickly coming due, he may lose his sister forever. Driven to desperation, Kai takes a gamble on an expedition into an unexplored Cube, risking everything for a reward that could change his fate. Can Kai arise from zero to hero and save his beloved sister? The answer may be right before his eyes...Suggested 15+

When the mysterious Cubes descended from the skies, humans gained access to magic, with each person’s rank determining their innate strength—and their worth. For Kai Amachi, a lowly Unranker with almost no magical power, life at the bottom means enduring the grunt work of dungeon expeditions for an uncaring party. But with his younger sister, Nagi, relying on him to cover her medical bills, giving up is not an option. Then disaster strikes when Kai is expelled from his party just as Nagi’s condition suddenly worsens. Unless he can pay the enormous hospital fee that is quickly coming due, he may lose his sister forever. Driven to desperation, Kai takes a gamble on an expedition into an unexplored Cube, risking everything for a reward that could change his fate. Can Kai arise from zero to hero and save his beloved sister? The answer may be right before his eyes...