After repelling the threat of a Neuroi invasion of Romagna and destroying the enemy's nest over Venezia, Yoshika Miyafuji returns to her hometown in the Empire of Fusou. Despite having lost her magical and healing abilities, the former officer of the 501st Joint Fighter Wing wishes to continue her medical studies. Her goal is to assist those in need, including both civilians and personnel on the front lines. She receives an invitation from a prestigious school in Europe and decides to accept it, setting off on a journey back to the war-torn continent. However, a new danger emerges as increasing numbers of Neuroi breach human defense lines, appearing unnoticed in supposedly safe zones and disrupting the balance of power in Europe. Yoshika's sense of duty clashes with her inability to pilot a Striker Unit, but with her friends in peril, it appears there is only one course of action she can take.