An Amakusa Catholic from a small village, she's developed genuine romantic feelings for Tōma—though her shyness keeps her from ever really acting on them or telling him how she feels. Over the course of the series she's traveled with him to Italy, France, and England, and by the 16th novel she's taken on the role of his caretaker.
When Acqua attacks, she's helpless to protect him. Her attempts to use magic to heal his wounds fail repeatedly because of his Imagine Breaker, and watching him get sent to the hospital nearly breaks her. Tatemiya Saiji eventually snaps her out of her despair by pointing out that moping won't help—she needs to be ready for when Acqua comes back, and she needs to prove to Tōma that protecting her was worth it.
That determination pays off. During the Amakusa Catholics' rematch against Acqua, she undergoes a dramatic shift—her whole demeanor changes, and she speaks differently, radiating a calm but terrifying fury. She unleashes a "Saint Destroyer" technique that damages Acqua badly enough to strip him of his "Divine Mother's Mercy."
Her weapon is a Friulian Spear. By layering magical reinforcement onto it, she can transform it into a "Thousand Years Tree"—a symbol representing plant growth that makes her magic spells more effective over time. She's also mastered a technique called Nanasen (七閃, "Seven Flash"), which she performs by manipulating both her spear and steel wires in a style similar to Kanzaki Kaori's fighting method.
Content compiled by AnimeList.moe from publicly available sources.
