In a future time of extreme overpopulation on Earth, explorations to seek out and inhabit other planets have taken flight. However, when the spacecraft known as the "Mesopotamia" experiences a mishap, the vast majority of its passengers perish, leaving only six men alive. These survivors make their way to a nearby planet dubbed "Terra II" which bears resemblance to their previous home. With unwavering determination to carry out their mission, these men establish six nations and employ techniques of cloning and genetic manipulation to ensure procreation. Despite their efforts, they are unable to obtain female inhabitants on this new planet, and so they create "Marionettes", female robots designed to carry out daily tasks and labor without emotion. This all changes when a young man named Otaru comes across three Marionettes equipped with the distinct "Maiden Circuit" which grants them the ability to feel. Otaru takes it upon himself to educate and nurture these sensitive beings, all the while protecting their country against a neighboring nation's aspirations of world domination, relying on his Marionettes to save their land.