Parona is a teenage girl of about fifteen years old from the village of Ninannah, where she lives alone and appears resourceful and independent. She has long black hair tied in a loose ponytail and wears a dress with cloth wrapped around her arms and legs. Her past is marked by tragedy: as a child she was chosen as a sacrifice for the village ritual, but her older sister tricked her into hiding in the woods under the pretense of a game and took her place, dying in her stead. Afterward the villagers shunned her, and she carried lasting guilt over her sister's death.

In personality, Parona is clever, observant, courageous, and selfless. She is practical and reserved, tending to prioritize clear judgment over emotion and showing her beliefs through actions rather than words. She strongly opposes the sacrificial tradition of Ninannah, having witnessed its cruelty firsthand. Despite her serious nature, she has a dry, self-deprecating sense of humor, especially about her archery skills and poor aim. Her main motivation is to protect the people she cares about, particularly March, and to prevent the same fate that claimed her sister from claiming anyone else. Her loyalty and sense of responsibility push her to keep fighting even in hopeless situations.

In the story, Parona serves as March's protector during the Ninannah arc. When March is chosen as the next sacrifice, Parona dedicates herself to stopping it, and the two eventually discover that the sacrificial ceremony is a ruse used by the foreign nation of Yanome to control and invade their homeland. Along with Fushi and the elder Pioran, Parona is captured and later escapes, but March dies during the pursuit while shielding Parona from danger. Parona carries March's body back to their village, and when the pursuers catch up, she shoots Hayase in the hand, though she despairs that her bad aim kept her from hitting a more vital target. Shortly afterward, Hayase captures and kills Parona and March's parents. Because Parona died near Fushi, he gains the ability to transform into her form, which he finds light and graceful and easy to move in. Later, Hayase reveals to Fushi that she was the one who murdered Parona, deepening the conflict between them.

Parona's most important relationship is with March, whom she treats like a beloved younger sister and tries to shield from the violence of the world. Her unnamed elder sister shapes her inner life, as the guilt of surviving her sister's sacrifice drives much of her resolve. With Fushi, she acts as an early guide, helping him understand human behavior and survival, and her eventual death makes her one of the forms he carries with him. Hayase is her central antagonist, a warrior whose fixation on Fushi leads her to destroy everything Parona tries to protect.

Over the course of her arc, Parona develops from a guilt-burdened and somewhat isolated girl into a determined fighter willing to confront danger directly, even when the odds are against her. She remains human throughout, with no supernatural abilities, but she is a capable archer who trains constantly, an agile and tactically minded fighter, and a skilled survivor in harsh conditions. Her defining strength is her willingness to sacrifice herself for others, and her death leaves a lasting impression on Fushi and the events that follow.