A world where the machine civilization has perished and immortal monsters called "Monotsuki" ("Possessed") are rampant. Isana, a girl born in a remote village, meets an android who lost her memories and looks exactly like her sister, who should have disappeared in the ruins she wandered into. Convinced that her sister is alive, Isana gives the mechanical person the name "Hime" ("Princess") and they set out together on a journey to find her sister.

Note: Volume ver consists of two oneshots previously released by the author and two sequel chapters, totalling four chapters. Hundreds of years have passed since a weather control satellite went haywire and started a war that destroyed the human race. After waking up from a long sleep, the android Laliberta met a clone girl named Speranza. Since Speranza could not live in the open air, the two interact with each other through a window... This is a series of stories depicting the thoughts and feelings of the girls surrounding the apocalypse.