TV-Series
Description
Itsuwa serves as a Japanese magician within the Amakusa-Style Remix of Church, an organization synthesizing Christian, Buddhist, and Shinto traditions via symbolic rituals and daily practices. Hailing from Shimabara, Kyushu, she likely spent most of her life there alongside her comrades. The group aimed to align with their former leader, Kanzaki Kaori, creating spells such as Saint Destroyer to comprehend her burdens as a Saint.

In appearance, Itsuwa is a teenage girl sporting shoulder-length black hair (depicted purple in visual media) styled in a bobcut with short fringes. She possesses light brown eyes and distinctive double eyelids. Her clothing emphasizes practicality for blending into surroundings, typically a sleeveless tank top with modified sweatpants or capris. During an Avignon mission, she wore skimpy attire after her clothes were soaked rescuing Kamijou Touma. Described as well-endowed, her physique is often termed "hidden" by comrades. Though her exact age is unspecified, placing her as a minor estimated around Touma's age, she demonstrates skills like piloting helicopters and driving motorcycles.

Personality-wise, Itsuwa exhibits warmth, humility, and modesty, frequently downplaying her abilities and appearance. She characterizes herself with unintentional humility, referring to possessing only "a hint of maturity" in charm. Pronounced shyness defines her, particularly around Touma, toward whom she harbors unrequited romantic feelings. These manifest subtly through gestures like offering hot towels rather than direct confessions. Unlike other female characters, flustered reactions avoid violence, favoring softer, lady-like responses. However, intense jealousy surfaces toward girls close to Touma, including Kanzaki, leading her to challenge her superior for his affection. Emotional volatility emerges during combat failures; failing to protect Touma from Acqua of the Back plunged her into despair and underage drinking until Saiji Tatemiya reprimanded her. This catalyzed a shift toward fierce determination, later displayed as "tranquil fury" in battle.

Itsuwa's combat abilities focus on teamwork and the Amakusa's signature Idol Theory, infusing symbolism into everyday objects and movements. Her primary weapon is the Friuli Spear, a five-part polearm disassembled for concealment and reinforced with spells like Reproductivity that Plants Possess. This layering technique amplifies durability by symbolizing tree growth, transforming the spear into an emblem of a "Thousand Years Tree." She employs diverse spells:
- Ley line disruption using found objects arranged in ritual circles.
- Offensive techniques such as Icy Night Wind (explosive force) and White Explosion (dual-location light bursts).
- Support spells include healing magic, damage-transference charms diverting injuries to clothing, and life-force concentration for power boosts.
- Unique to her is Saint Destroyer, a collaborative spell requiring Amakusa unity. It exploits Saint vulnerabilities via Idol Theory, referencing the Lance of Longinus. Itsuwa activates it using a towel-wrapped spear to reduce friction, generating cross-shaped energy to immobilize or harm Saints. She also replicates Kanzaki's Nanasen technique—renamed Seven Blades of the Seven Teachings—using wires with her spear for multidirectional strikes.

Her development unfolds across missions in Italy, France, and England alongside Touma. During the Orsola Aquinas rescue, she fell in love with him, though shyness prevented overt expressions. In Volume 16, she became Touma's caretaker and bodyguard. After Acqua critically injured Touma, Itsuwa failed to heal him due to Imagine Breaker negating her magic, triggering guilt-induced depression. Following Saiji's intervention, she refocused on combat readiness. During the Amakusa's rematch against Acqua, her resolve hardened into controlled rage; she executed Saint Destroyer successfully, stripping Acqua of his Divine Mother's Mercy and enabling his defeat. This arc marked her evolution from a reticent supporter to a pivotal combatant.