Queen Xanthia is the stepmother of Snow White and the central antagonist of the anime The Legend of Snow White, appearing under different names in various language versions of the series. She comes from a small neighbouring kingdom and arrives at the Emerald Valley to marry King Conrad after the death of his first wife, Queen Isabelle, whose dying wish was that her daughter be raised by a new mother. At first, Xanthia presents herself as a loving and caring guardian, and the king entrusts his daughter to her when he is forced to leave for war. Once he is gone, however, her true nature emerges and she makes Snow White's life increasingly difficult before eventually driving her from the castle.

Xanthia is intensely vain and places her own beauty above everything else. She is described as evil, selfish, and ambitious, and she is deeply devoted to the idea of being the fairest woman in the land. This obsession shapes nearly all of her actions, and she is willing to go to any lengths to preserve her position and her appearance. She also practices sorcery, using black magic to support her schemes and to pursue her goals.

Her primary motivation is jealousy. When her magic mirror reveals that the young Snow White has become more beautiful than she is, Xanthia decides to eliminate her stepdaughter. Her attempts on Snow White's life are repeated and varied. She tries a poisoned ribbon, then an enchanted comb, and each time the seven dwarfs are able to save Snow White with the help of their Book of Knowledge. Her final effort involves a poisoned apple, which succeeds in placing Snow White in an enchanted sleep. It is revealed at this point that her goal was not simply to kill the girl but to take over her body. Xanthia's own body has been aging rapidly because of her continued use of sorcery against a pure soul, and she intends to transfer her spirit into Snow White's healthier and more beautiful form.

In terms of her role in the story, Xanthia is the force that sets the entire plot into motion. By forcing Snow White to flee the castle, she sends the princess into the forest, where she meets the seven dwarfs and begins a new life in hiding. Xanthia remains a persistent threat throughout the series, repeatedly pursuing her stepdaughter and endangering the small community that has taken her in.

Her key relationships are defined by this conflict. With Snow White, she is a cruel and jealous stepmother who sees the girl only as a rival. With King Conrad, she is a deceptive wife who betrays his trust while he is away at war. She also has a significant connection to the spirit of her magic mirror, which is bound to answer her truthfully about who is the fairest in the land. This mirror spirit plays a crucial role in her downfall, as it is eventually revealed that the spirit is an evil entity that has been controlling her mind and actions since she was a child. Prince Richard, who loves Snow White, confronts the evil spirit and defeats it with the help of the four elements.

Her development leads to a genuine turn late in the series. Once the mirror's evil influence is broken and she is freed from its possession, Xanthia is no longer the cruel queen she had been. She is shown to be redeemed, and the ending of the story is marked by reconciliation and joy, especially with the return of the king. Her most notable abilities are her magical powers, including the creation and use of enchanted objects such as the poisoned ribbon, the bewitched comb, and the poisoned apple, as well as her ability to disguise herself and her command over the truth-telling magic mirror.