Eimugai

A high school girl named Minon discovers that her brother has vanished, leaving only an email claiming he was kidnapped by a serial killer named "A" and mentioning a place called "Eimugai." Determined to find him, she enters a suspicious building where she last saw him, only to realize it leads to a restricted area that should not be accessed. She becomes trapped in a location filled with an overwhelming force of evil that defies logic and comprehension. The story follows her efforts to navigate this dangerous and inexplicable environment in a desperate attempt to rescue her brother.