TV-Series
Description
Mia Adenauer is the younger sister of Philia Adenauer, born into a family with a long lineage of Saints responsible for protecting the kingdom of Girtonia from monsters. As the second Saint in her generation, she is widely beloved by the citizens for her radiant smile and amiable personality, contrasting with her sister's perceived aloofness.

Despite being favored by her parents and the public, Mia genuinely admires and cares deeply for Philia, maintaining an obsession with her older sister and a warm relationship that subverts expectations. When Philia is abruptly sold to the neighboring kingdom of Parnacorta without Mia's knowledge, Mia reacts with shock and betrayal. Discovering the truth, she develops a strong loathing for Prince Julius and her parents due to their mistreatment of Philia.

Mia initially struggles to fill the void left by Philia as Girtonia's sole Saint. While acknowledged as capable, her magical barriers are weaker than Philia's, though she casts spells faster. Their predecessor, Hildegard, believes Mia has the potential to eventually match or surpass Philia's power with continued training. Facing impending disaster without Philia, Mia devises a revenge plan against Julius and her parents. She pretends to accept Julius's marriage proposal while secretly conspiring to undermine his claim to the throne, aiming to install the first prince, Fernand, as king instead.

Himari, a ninja servant assigned to Philia in Parnacorta, aids Mia in her schemes after Philia requests Himari protect her sister. During an excursion with Julius, Mia witnesses his cowardice firsthand when he uses her as a shield during a demon attack, solidifying her resolve against him. Concurrently, Hildegard—revealed as Philia's biological mother—learns of Mia's plans and initiates legal proceedings to adopt her, anticipating the downfall of Mia's adoptive parents, Georg and Cornelia Adenauer, once their misconduct becomes public.

Mia's character arc emphasizes her loyalty to Philia and her growth from a comparatively inexperienced Saint into a strategically adept figure navigating court politics. Her actions consistently prioritize protecting her sister's legacy and seeking justice against those who betrayed Philia.