Siegfried Marquez is a court magician and personal bodyguard to King Diseum von Earlshide of the Earlshide Kingdom. He sports silver hair and blue eyes, typically dressed in magician robes. Though generally easy-going, Siegfried frequently engages in fiery arguments with fellow court magician Christina Hayden whenever they meet. These clashes often require intervention from others like Melinda Bowen or Michel Collins to stop, especially if they occur near Shin Wolford. Recognized as a highly capable magician suitable for protecting the monarch, Siegfried faces restrictions on advanced magical training. Prince August von Earlshide expressly forbids him from adopting Shin Wolford's revolutionary magic-casting techniques due to military concerns, despite the kingdom utilizing Shin's other innovations like detachable blades. During joint knight-magician field exercises, Siegfried mentors magician students while Christina trains knight trainees; both are responsible for Prince August's safety. In combat against demonic threats, Siegfried proves competent but operates at a different level than Shin, visibly shocked witnessing Shin instantly defeat a Calamity-class demon. His relationship with Christina remains contentious due to professional differences. Conversely, he develops a protective, almost brotherly rapport with Shin, treating him with familiarity and concern. Siegfried illustrates the institutional limitations of royal magicians, contrasting Shin's unconventional methods, and supports world-building through his presence in training arcs and demon-response operations involving the kingdom's military and magical structures.