Pauline hails from Talwess in Viscount Boardman's domain, where her parents ran the Beckett Company. Thieves, orchestrated by the company's head clerk, ransacked their shop, resulting in her father's death and forcing her mother to sign ownership documents under duress. Her stepfather subsequently enrolled her in Hunters' Prep School, seeing her potential as an asset for advantageous social or marital connections.

Outwardly shy and dutiful, Pauline possesses a dual nature. She meticulously manages finances for her hunter party, the Crimson Vow, viewing currency as a pragmatic transactional tool. Yet, she harbors fierce protective instincts, manifesting cold calculation and sadistic tendencies when friends or family are threatened. This ruthless facet, earning her a "wicked" or "evil" reputation, surfaces in dealings with dishonest merchants or adversaries, often conveyed through politeness or a "smile that barely hides malice." Her noticeable bust size at age 15 causes self-consciousness among peers, though she deliberately avoids leveraging it for mercantile gain.

Specializing in water and healing magic, Pauline's abilities extend beyond convention. Her repertoire includes restorative spells like Heal and Mega Heal, offensive techniques like the explosive H-Bomb and pressurized Water Cutter, and environmental manipulations like Slippery. She innovates non-lethal combat using capsaicin-infused spells—Blinding Mist, Ultra Hot Mist, and Ultra Super Deluxe Hot Tornado—to incapacitate foes through intense irritation. Her strategic "Shadow-Casting" allows subtle spell-weaving during conversations. Official media depicts variations in her power portrayal; the anime reduces her combat intensity compared to the source material, where she demonstrates extreme pragmatism, such as shattering an examiner's arm and instantly healing it during a test.

Her character arc centers on avenging her father. With the Crimson Vow's support—particularly Mile's interventions and Mavis von Austien's noble connections—Pauline confronts those responsible for her family's ruin. This culminates in a sanctioned duel where she defeats the Beckett Company president and Viscount Boardman, reclaiming her legacy. Following this resolution, she transitions from vengeance-driven pursuits to fully embracing her role within the Crimson Vow. She retains her financial acumen and occasional teasing of allies, like exploiting Mile for novel product ideas, but her interactions show increased trust and camaraderie, balancing earlier severity with lightheartedness.

Physically, Pauline has medium-length brown hair styled in a braided crown, violet eyes, and a notably busty figure. Her signature attire is a flamingo-pink dress with black trim and cyan wavy accents, paired with thigh-high socks and brown shoes.