When interdimensional travelers from an otherworldly land known as "Japan" appear, death and destruction always follow. It's up to Executioners like Menou to exterminate the Lost Ones before they wreak havoc. When Menou encounters a Lost One named Akari, it's bloody business as usual... until Menou discovers Akari can cheat death. Even so, Menou has a job to do, and she is committed to her executioner's mission come hell or high water - provided her newly stirring feelings don't get in the way.