Kai Shinjo, an ordinary high school student by day and a deadly assassin by night, hides behind his quiet, dark demeanor, making him an outcast among his classmates. One day, his entire class is transported to another world — a realm of swords and magic. There, a woman named Leonora reveals they were summoned as Hero candidates to defeat the Demon Lord. Each student receives a Blessing, but Kai’s power, Appraisal, seems useless compared to others’. Yet, with his assassin’s skills and cold precision, Kai begins to move in the shadows of this new world.