The story revolves around a doll called "Hybrid Child" which grows reflecting the owner's affection. Kotarou Izumi, who is the 16th head of the noble Izumi family, found a hybrid child at the garbage disposal spot when he was eight years old. He has lived with the doll named Hazuki for 10 years since then. However, Kotarou learns Hazuki's life is close to the end. (Crunchyroll)