Orphaned young, Priestess (also called Onna Shinkan) was raised in an Earth Mother temple, training in priesthood and learning divine miracles. At fifteen, she became a porcelain-ranked adventurer to aid others. Her first party underestimated a goblin extermination quest; ambushed, the men were slaughtered and the women assaulted before being killed. Paralyzed by fear, she awaited death until rescued by Goblin Slayer, forging a lasting bond. She became his first permanent party member.

Initially kind, empathetic, and shy, she appeared delicate and cried easily, particularly distressed by Goblin Slayer's methods. Early vulnerability caused breakdowns in danger, like in Water Town's catacombs. Over time, exposure to his pragmatic tactics fostered resilience. She grew assertive, maintaining composure even while tearful, and learned to wield her defensive miracles with strategic creativity. Party members noted her tactical thinking resembled Goblin Slayer's, exploiting enemy weaknesses.

Her Earth Mother-granted abilities focus on defense and support: Minor Heal (minor injuries only, ineffective against poison/vitality loss), Protection (magical barriers for defense or confinement), Holy Light (blinding flashes), Purify (removes impurities, cleanses, disrupts blood-based evil magic – transmuting a goblin shaman's blood to water violated divine principles, earning a warning), Silence (sound-dampening fields), and Sanctuary (purified safe zones). She can cast only three per day, adapting them resourcefully beyond their intended purpose under Goblin Slayer's guidance.

Standard equipment includes a Sounding Staff for miracles, a sling, and chainmail worn beneath robes. She treasures the chainmail, her first purchase after joining Goblin Slayer, which earned his praise for practicality. She briefly used a flail during the Harvest Festival and against the Dark Elf but found it unwieldy after self-injury during training.

Her journey spans multiple arcs: confronting trauma through continuous goblin hunts with Goblin Slayer, rising to obsidian then steel rank. She immobilized the Goblin Lord with Protection, enabling his defeat. She mentored the Princess after the royal was kidnapped by goblins using stolen vestments; post-rescue, the Princess converted to the Earth Mother faith, inspired by Priestess's compassion. Later, Priestess supervised the Princess inspecting a practice dungeon during a festival. They encountered the Hero's disguised party; the Princess temporarily joined them as priest, aided Priestess in subduing a rogue sorcerer, and admired her resolve.

Her path reflects a transition from fragility to steadfastness, driven by preventing others from suffering as she did. Her faith, occasionally shaken by moral dilemmas like miracle ethics, remains core, motivating her to protect and heal amidst relentless darkness.