Towa originates as the sentient sword "Twilight," an immensely powerful weapon capable of assuming human form. This transformation into a young girl allows her to directly confront her wielder, Takeshi Nanase. Manifested this way, Towa challenges Takeshi about the sword's history, revealing that all previous owners succumbed to an obsessive lust for power, thereby testing Takeshi's character and motivations.

Initially existing without a personal name and referred to solely as "Twilight," the weapon gains its identity when Takeshi renames it "Towa" – meaning "eternity" in Japanese. This act symbolizes Takeshi's rejection of the sword's destructive legacy and his commitment to wield it without falling into the corrupt patterns of prior wielders. The naming visibly pleases the manifested entity, signifying newfound trust and acceptant of Takeshi as a different kind of master.

Her physical manifestation as a girl possesses lilac or blonde hair and violet eyes. This form embodies the sword's consciousness, enabling direct interaction and dialogue about its nature and expectations.

Towa's core narrative function lies in highlighting Takeshi's moral divergence from Twilight's previous users. By embodying the sword's sentience, she becomes the catalyst for Takeshi to consciously reject a path of power-seeking corruption. Her acceptance of the name "Towa" marks a pivotal moment signifying Takeshi's successful establishment of a relationship based on mutual respect rather than domination, contrasting sharply with the sword's past. Her role remains focused on the initial confrontation and naming, establishing the bond with Takeshi.