Lumiale holds the position of Guardian of Water, a foundational cosmic power essential for universal balance alongside eight other Guardians within the Angelique universe. Under the Queen's guidance, he oversees the flow and abundance of water throughout the cosmos.

Physically, he features long blue hair, blue eyes, a height of 183 cm, and a slender build weighing 57 kg. His documented age is 21 across multiple core titles. Lumiale's personality embodies traits associated with water: kindness, refinement, and a calm demeanor, reflecting his role in nurturing stability and harmony.

He appears as a main character and potential romantic partner in the inaugural 1994 *Angelique* game, where candidates interact with Guardians during the Queen Examination. He retains this capacity in subsequent titles including *Angelique Special 2*, *Angelique Tenkuu no Requiem*, *Angelique Trois*, and *Angelique Etoile*. His consistent function across these appearances is supporting the cosmic order through his elemental domain while offering narrative pathways for romance or alliance within the games' dual-ending structures.