Years after Haruko's arrival, a war erupts between Medical Mechanica and Fraternity. Hidomi, a student, meets her new teacher Haruko. When Mechanica attacks, Hidomi awakens a power only Haruko can unleash to protect everyone.

Many years have passed since Naota and Haruhara Haruko shared their adventure together. Meanwhile, the war between the two entities known as Medical Mechanica and Fraternity rages across the galaxy. Enter Hidomi, a young teenaged girl who believes there is nothing amazing to expect from her average life, until one day when a new teacher named Haruko arrives at her school. Soon enough, Medical Mechanica is attacking her town and Hidomi discovers a secret within her that could save everyone, a secret that only Haruko can unlock.