Mai Kazuki, a young girl from a magician family, grows up in the Magic Carat troupe led by her grandparents, with her mother as a former performer. She dreams of matching her idol Emily Howell's skill but faces constant setbacks from her inherent clumsiness and self-doubt. Her path shifts when she discovers Topo, a mirror fairy dwelling in her stuffed flying squirrel doll. Topo gifts her a magical bracelet that summons a wand, allowing Mai to transform into her older, teenage persona, Magical Emi. This metamorphosis erases her clumsiness and grants genuine magical powers, elevating her stage performances.

As Magical Emi, she headlines Magic Carat's shows, wielding magic to dazzle audiences and resolve real-world challenges. Yet her success feels hollow, as it stems from enchantment rather than personal ability, sparking deep internal conflict. Driven by a desire for authentic achievement, she ultimately renounces her magical powers, choosing to pursue her original dream through dedication and practice.

In the crossover OVA "Majokko Club Yoningumi: A Kuukan kara no Alien X," Magical Emi allies with three other magical girls—Yuu (Creamy Mami), Persia (Fairy), and Yumi—against an alien menace. The team battles a monster that rapidly ages young women, a mission demanding travel into space. Mai deploys her magic alongside the group, with Yumi supplying specialized space suits, demonstrating her role in a wider magical universe.

Key relationships shape her journey: she shares a sibling-like dynamic with troupe-mate Sho Yuki, blending playful rivalry with steadfast support. Unaware of classmate Musashi Koganei's affection, she remains focused on her magical ambitions. Her younger brother Misaki tests her patience yet awakens her protective instincts, reinforcing her identity as a devoted older sister. Through these experiences, Mai evolves from a child dependent on magic to a resilient individual committed to genuine growth.