Jinzou Majo wa Hito ni Arazu

Artificial witches are weapons. Created from a single corpse and a single magic stone, they were deployed on the battlefield as weapons capable of wielding magic. After the war, having fulfilled their role as weapons, they hid deep within the forest in search of a place of refuge. There, they lived out their days in peace until the magic remaining in their magic stones was exhausted. While many of the Artificial Witches accepted this slow death, Mia, who had less magic left than anyone else, feared death and stole the magic stone of Anneliese, the first Artificial Witch who had been enshrined as a deity.

(Source: Comic Walker, translated)