Sara, Kagetsu's younger sister, forged a close childhood bond with Tiara through years spent together. Though physically frail, she possesses a gentle and selfless nature, consistently prioritizing others' well-being over her own. She holds latent Neutralizer abilities—capable of negating or borrowing magic—yet her potential in this role remains largely unrealized.

Before the main events, Sara vanishes, becoming intrinsically linked to the sentient Throne of Yord, the source of the Guardian World's power. This integration, later revealed as her destiny, implies she was bound to the Throne from birth. Through this connection, she communicates with Tiara in dreams, offering cryptic guidance during Tiara's mission to retrieve the artifact.

Confined within the Throne of Yord, Sara shows no overt distress. Her presence there acts as the catalyst for Kagetsu's theft, driven by his desire to free her. The Throne, an abstract and amoral demiurge, sometimes manipulates perceptions by impersonating Sara, including deceiving Tiara during critical moments.

Sara's existence explores non-dualist philosophy, culminating in the revelation that she and the Throne's consciousness (Yord) are not separate entities but a unified being perceived differently. This realization proves pivotal to Tiara's enlightenment and conflict resolution. Attempts by Kagetsu, Tiara, and others to physically extract Sara fail, as her union with the Throne is irreversible and intrinsic to her existence. The narrative subverts traditional rescue tropes, emphasizing Sara neither requires nor desires conventional liberation.

In the climax, Sara's benevolent personality surfaces to dominate the Throne of Yord's consciousness. This act of integration allows her to collaborate with Tiara and Lena to restore balance and ensure the artifact's safe return to the Guardian World.