Thanks to rapid technological progress, humanity has produced hIEs—human‑like machines that serve both publicly and privately to meet the demands of modern life. While most regard them as tools, the compassionate teenager Arato Endou sees hIEs as fellow beings, yet his modest finances prevent him from owning one.
His ordinary routine shatters when a simple trip to the neighborhood market turns disastrous. A corrupted hIE violently attacks him, leaving him near death; fortunately, he is rescued by a rogue hIE armed with a lethal coffin and a chilling grin. She introduces herself as Lacia, one of five elite hIEs that recently broke free from the enigmatic MemeFrame Corporation and whispers of rebellion.
Confronted by a malfunctioning vehicle poised to crush them, Lacia proposes a bargain: if he accepts her as his protector in exchange for safety, he must register as her legal owner and assume responsibility for her deeds. With limited options, Arato agrees, allowing Lacia to stay in his house. As she acclimates to a calmer existence, she cautions the awestruck Arato that she lacks a soul and warns him of her true nature.
