The story tells about a "lost man" from Japan in a different world. In the past, he brought disasters that could destroy the world and had to be secretly executed. Menou, who makes a living as an "executioner", meets a Japanese girl named Akari one day, but fails to execute her because of Akari's special ability. In order to find a way to kill Akari, Menou and his partner embark on a journey together, which gradually changes their relationship. The original novel was written by Sato Shinto and illustrated by Niritsu. It began serialization in 2019 and won the Grand Prize at the 11th GA Bunko Awards.