Melpha is a character who serves as a priestess in Gainos, the capital city of the continent. She is a human deeply devoted to her faith and runs a church, where followers consider her a holy woman or a saint due to her virtuous and kind nature. Melpha belongs to a fundamentalist religious sect that follows ancient scriptures, and she is the granddaughter of the sect's fanatical leader, Cardinal Dantan.

In terms of appearance, Melpha has long blonde hair and blue eyes. Her height is approximately 166 centimeters. Her attire typically consists of a blue cap with a white metal front piece engraved with a religious symbol, a long blue dress worn over a white bodysuit, a purple cloth wrap, a beige corset around her waist, and brown calf-high heeled boots.

Melpha's personality is characterized by shyness, humility, and a calm disposition. She is deeply pious and dedicated to her religion, though her gentle and impressionable nature makes it difficult for her to voice her discontent openly. This internal conflict is a central aspect of her character, as she often finds herself bound by the expectations of her grandmother and the believers who admire her. Despite her personal embarrassment, she remains committed to her religious duties and helping others, even when her generosity leaves her vulnerable to exploitation.

The primary motivation driving Melpha's role in the story is her forced participation in the Queen's Blade tournament. She is sent to compete as the unwilling representative of her religious sect, fulfilling the orders of her grandmother despite her own misgivings. Her journey to the tournament marks her first time traveling alone, and she often encounters people in need, whom she assists by giving away her possessions or performing her holy rites.

A key relationship in Melpha's life is with Nanael, a self-proclaimed angel. Melpha is greatly devoted to Nanael, whom she reveres as a divine messenger sent from the Heavens to help her become a better priestess. This relationship highlights Melpha's impressionable and faithful nature, as she accepts Nanael's claims without question. Her loyalty remains steadfast even when Nanael becomes a Fallen Angel, as Melpha defends her and ultimately helps restore her to a Pure Angel.

Melpha's role in the story is defined by the tension between her personal dignity and her religious duty. Her most notable ability is the use of Divine Power, a form of white magic that manifests as a heavenly punishment on her opponents. To channel this power, she must perform anachronistic rituals known as Holy Poses, which are described in her sect's ancient scriptures. These poses are considered ridiculous and lewd in modern times, and Melpha finds them deeply embarrassing to perform, especially in front of others. Despite having minimal conventional fighting ability and relying on a small buckler and a spiked mace that she rarely uses, her offensive powers through these poses are exceptionally potent. They are particularly devastating against the undead, with Melpha once able to wipe out all undead creatures around the entire capital of Gainos in a single burst of holy energy. While her sect secretly knows that priests can manifest Divine Power without these poses, this knowledge is kept from groups like hers, leaving Melpha with no choice but to endure the humiliation. Her combat statistics rate her low in attack, agility, and technique, but higher in defense. Over the course of her story, Melpha's development sees her struggling to reconcile her spiritual obligations with her personal sense of shame, even as she remains a kind and faithful priestess dedicated to protecting others from evil creatures.