Written by novelist Koji Dogu and illustrated by chibi, takes place 100 years after a fictional “great fire” which left a cluster of mysterious illegal structures now known as Tekkai Jousai (fortresses) burnt to crisps. Yuuma Kuze, an archeologist commissioned to investigate the place, discovers a girl named Haika among the ruins. Progressing through the story, you will have to uncover the mystery of the forest, investigate the “treasure for death” which Haika is looking for, and find out the truth about Haika herself.