In the anime, Maggie, whose full name is Meg Kanzaki, is introduced as a powerful young witch from another dimension who is sent to Earth as part of her training to become the next queen of the Witch World. Her background is immediately marked by the magic used to integrate her into human society; her adoptive mother, Mami Kanzaki, a former witch who chose to stay on Earth for love, uses her powers to bewitch her human husband and their two young children, Rabi and Apo, into believing that Maggie has always been the eldest daughter of the family. This sets the stage for Maggie to navigate not only the trials of a magical apprenticeship but also the unfamiliar and often chaotic dynamics of family life and school.

Personality-wise, Maggie begins as a brash, hot-tempered, and somewhat selfish teenager, a classic bratty teenage daughter struggling to adjust to her new environment. She has a fiery temper, is physically aggressive, and is prone to fighting with the school bully as well as squabbling with her mischievous younger siblings, who constantly play pranks on her. Despite her often foul-mouthed and impatient exterior, she possesses a strong sense of justice and a genuine, caring heart. Her core motivation is to prove herself worthy of the throne by learning to control her powers and impulses, but more than that, she discovers a deep-seated desire to understand and protect the people around her, often finding herself standing up against villains who threaten innocent lives. This internal conflict between her selfish impulses and her heroic nature is a primary driver of the story.

Maggie's role in the narrative is that of the central protagonist, a free spirit who is a contender for the crown but also a complete fish out of water, needing to learn lessons about humanity that her magic alone cannot teach. Her key relationships are fundamental to her development. Her relationship with her rival, Non, is particularly significant. Non, a blue-haired, cold, and highly skilled witch, is the other contender for the throne and initially tries to kill Maggie. Over time, their intense rivalry evolves into a complex dynamic of grudging respect, and they occasionally team up against common enemies like the evil witch-queen Saturn, forming an uneasy truce. At home, her interactions with her adoptive family are crucial. She constantly clashes with her prankster brother Rabi and younger sister Apo, but gradually evolves into a cool big sister figure who cares for them deeply. Her adoptive mother, Mami, serves as a gentle, level-headed mentor and secret-keeper, the only one who knows Maggie's true origin, while her father, Papa, is a stern but loving muggle parent who helps ground her in human norms.

Throughout the series, Maggie undergoes significant character development, maturing from a willful, temperamental girl into a more giving, thoughtful, and compassionate young woman. She learns to experience and express a range of new emotions, including loneliness, grief, love, and self-sacrifice, which ultimately prove the nobility of her character. Her journey is one of learning that her true enemy is often the darker side of human nature rather than a magical monster. As for her notable abilities, Maggie is an accomplished witch skilled in both magic and hand-to-hand combat. She typically uses a heart-shaped necklace as a necessary tool to cast her spells. Her iconic magical item is an umbrella, which she famously uses as a parasol parachute to fly down to the human world in the first episode. While she is powerful, she is also described as accident-prone, and she often uses her magic for mischievous purposes like hiding when she is late for school, before learning to wield it more responsibly for the sake of others.