Kadsuki Mai is your average 11 year old girl. She works with her family as a part of the "Magi Carat" Magical group. Still a magician in training, Mai has yet to master the art of performing magical tricks with success. She is a rather inept magician, though she tries very hard. The series begins with Mai and her family moving into a new house. While unpacking the boxes in her new room, Mai comes across a heart-shaped mirror. When she looks into the mirror, Mai suddenly sees her reflection repeated hundreds of times, and is drawn into the magical Mirror World. In the Mirror World, she is given several magical items.
When she returns from the Mirror World, Mai finds herself in possession of the Magical Mirror, along with a bracelet. To top it off, one of the Mirror Faeries, Topo the flying squirrel, is there with her. Mai is a bit confused, but extremely happy with her new items, which allow her to transform into an older, pretty girl whom she decides to call "Emi-chan", after a Magician she idolizes named Emily.
Mai isn't doing too well in her work with the family magical act. She keeps messing up, showing signs of the Magical Girl clutziness. During one particularly disastrous performance, Mai transforms herself into Magical Emi and performs fantastic feats of magic. Stunned by the cute young girl's amazing powers, the crowd applauds wildly, and the magical show is a hit. Mai, as Magical Emi, is now part of the act!
The object of Mai's shy interest is a 16 year old boy named Syou Yuuki. He is a handsome boxer. Mai often goes to his boxing matches to cheer him on.