In a post-apocalyptic future governed by "Numbers," each human's identity will be branded with their own "Count," which might identify any number linked to their existence. This Count, whether it be one's traveled distance or the number of praises offered to them by others, might lead them to the abyss when it reaches zero. Hina has inherited a quest from her Mother, whose Count has depreciated to zero, to find the Legendary Red Baron in the year 305 of the Alcian calendar. During her quest, she meets a half-masked swordsman named Licht, who attempts to conceal his identity because he is considered a degenerate because to his extremely low Count.