Yvette L. Lehrman, a student of the El-Melloi Classroom at the Clock Tower, hails from the Lehrman family, famed artificers of gem-crafted Mystic Eyes indistinguishable from natural variants. Her right eye socket houses multiple interchangeable Mystic Eyes concealed under a star-shaped eyepatch: Malachite for Emotion Sight, Ruby for flame manipulation, Iolite for tracking magical energy, and Gold for compulsion, alongside four others. To wield eight distinct Eyes, her brain endured sevenfold modifications—a perilous process bordering on madness—that underscore her formidable mental resilience.

Flamboyant and cunning, Yvette openly declares herself a spy for the Neutral Faction’s Meluasteas, weaving strategic deception with theatrical charm. She taunts Lord El-Melloi II with faux-romantic provocations, leveraging his reactions for tactical gain. During the Mystic Eyes Collection Train crisis, she aids in repairing the Rail Zeppelin’s sabotaged leyline, deploying her Flame Eyes to incinerate vampiric flora and Iolite Eyes to pinpoint magical disruptions. Partnering with Melvin Weins, she temporarily amplifies her capabilities through his Magic Circuit enhancements.

In the Grand Roll arc, Yvette compiles historical records on the Clock Tower under El-Melloi II’s orders, employs Emotion Sight to unmask deception in factional disputes, and engages in clashes with rogue supernatural entities. Her role in *Fate/strange Fake* sees her accompany the El-Melloi delegation to Snowfield after Flat Escardos’ demise, though Verner distrusts her volatile allegiances, denying her Command Spells. Her narrative threads intertwine espionage, academic rivalries, and the moral ambiguities of artificial Mystic Eyes, balancing her identity as a gifted magecraft scholar and a shrewd political operator navigating the Clock Tower’s fractious factions.