Mankind's great technological advancements have led to the creation of hIEs, which are human-like robots designed to serve society both publicly and personally. However, due to his financial situation, the kind-hearted high school student Arato Endou cannot afford to own one, even though he treats them as equal beings. One day, while running errands at the local grocery store, Arato's life takes a dramatic turn. He is brutally attacked by a hacked hIE and is left on the brink of death. Fortunately, he is saved by an extraordinary hIE named Lacia, who is armed with a weaponized coffin. Lacia is one of the five highly advanced hIEs that recently escaped from the enigmatic MemeFrame Corporation. As they are being chased by a hacked car, Lacia offers Arato a deal—he must register as her new owner in exchange for saving his life. This means that he is fully responsible for her actions. Arato agrees, and Lacia moves into his home. Despite adjusting to her new peaceful life, Lacia warns Arato that she does not have a soul.