Anya Dostoyevskaya is an undine trainee with Orange Planet, apprenticed to Alice Carroll. She trains alongside fellow trainees Ai Aino from Aria Company and Azusa B. McLaren from Himeya Company, forming a close-knit group dedicated to honing their skills as gondolier guides in Neo-Venezia.

Her personality blends calmness and spontaneity. She occasionally employs a literary tone in her speech, suggesting thoughtfulness. This demeanor informs her interactions within the group during training and joint activities.

In "Aria the Benedizione," Anya participates in winter training exercises with Ai and Azusa. During one session, they encounter Akira E. Ferrari behaving unusually, who later invites them to the Undine Museum. There, they meet Asuka, Akira's senior, the museum director, and a legendary figure from Himeya Company. The visit centers on a gondola preserved since Himeya's founding, intended for inheritance by Aika S. Granzchesta. When Aika expresses reluctance, Anya observes Azusa trying to understand Aika's perspective. Later, Anya joins Ai and Azusa in seeking Akari Mizunashi's help to organize a group gondola ride with Aika, aiming to address the concerns about tradition and legacy.

Throughout this narrative, Anya's role is primarily supportive. She accompanies her peers during significant events, including the resolution of Aika's internal conflict about the gondola inheritance and her subsequent Prima Undine exam. Her presence reinforces the camaraderie among the younger generation of undines as they navigate respecting established traditions while forging new paths.