Jolenta is a young woman who becomes a central figure in the pursuit of heliocentric theory, first appearing as a fourteen-year-old prodigy working at an astronomical institute. She is introduced as a character of remarkable intelligence and passion, yet she is immediately confronted with the systemic misogyny of her 15th-century setting. Despite being admitted to an esteemed institute under a leading scholar, she is denied meaningful research opportunities, excluded from discussions and lectures, and prevented from publishing her work under her own name solely because of her gender. Her peers are cruel to her, and even her assistant, Kolbe, takes credit for her brilliant essay by submitting it as his own to Count Piast, rationalizing that an essay by a woman would be considered dangerous and could lead to accusations of witchcraft.

Jolenta’s personality is defined by a potent mix of defiant nerdy passion and a practical sense of self-preservation. She is endearingly enthusiastic about her studies, finding a rush in what she considers rebellion, such as secretly doing advanced homework. She cannot bring herself to quell her passion for science, even when everyone around her advises her to keep her head down. This conflict between her burning curiosity and the need for secrecy shapes her early actions. For instance, she secretly eavesdrops on academic discussions by climbing down a dried-up well to overhear lectures from a room below. Her father, who is later revealed to be the ruthless Inquisitor Nowak, encourages her studies but also tells her not to attract attention, a lesson that initially makes her fearful and leads her to lie about her own intellectual achievements.

Jolenta’s motivations stem from a deep-seated need for intellectual acknowledgment and a genuine love for the truth. When she sees a complex astronomical problem posted on a bulletin board by the heretical researchers Badeni and Oczy, she is driven to find the solution, doing so in half a day and posting the answer under a man’s name to avoid repercussions. This act brings her into their fold. Her role in the story evolves from a suppressed talent into a key partner in the heretical research. She agrees to work with Badeni and Oczy, leveraging her access to the institute’s observations to help fill the gaps in their theory. Her presence creates a direct and ironic conflict with her father, Nowak, who has rationalized his brutal persecution of heretics as a way to secure a peaceful world for his daughter, unaware that she has become one of the very heretics he hunts.

Jolenta’s key relationships are complex and define her journey. Her relationship with her father, Nowak, is the most pivotal. She is unaware of his profession as an inquisitor, and he is unaware of her secret life. When Nowak’s apprentices torture and execute Badeni and Oczy, they reveal Nowak’s true identity to Jolenta. She is then subjected to interrogation and torture herself, during which a sympathetic apprentice helps her escape upon discovering that a church official has a personal vendetta to frame her as a heretic to ruin Nowak. Her relationships with Badeni and Oczy are initially based on manipulation and mutual need, as Badeni sees her as a useful asset, but they evolve into a collaborative partnership united by their pursuit of knowledge.

Jolenta undergoes significant development, surviving the Inquisition's purge to become a leader of the movement of freethinkers. Twenty-five years after the events of her youth, she holds a position referred to as Director of the Organization and serves as a mentor to Draka, the protagonist of the story's third chapter. In this later role, she stands in direct opposition to her biological father, Nowak, though her feelings of caring for him have not entirely changed. She engages in deep conversations with religious characters, not with blind hatred but with a logical foundation, aiming to change minds rather than simply prove a point. Her existence ensures the continuity of the scientific research, passing the torch of heliocentrism to the next generation and ultimately being credited as the author of the in-universe book On the Movements of the Earth.

Jolenta’s most notable abilities are her extraordinary intellect and her skill in navigating a hostile environment. She possesses one of the brightest minds in her institute, capable of solving difficult problems that stump others, and she can work with complex astronomical records and theories with ease. Furthermore, she develops a keen sense of which battles to pick, a skill likely learned from being the daughter of a powerful and dangerous man. She knows how to communicate ideas effectively and can work in secret, demonstrating a resilience and strategic thinking that allow her to survive and eventually lead a movement.