Meimi's a bright and cheerful girl, who inherited her father Genichiro's magic powers and her mother Eimi's abilities as a thief. Now at night she turns into the mysterious thief Saint Tail and sets about town righting wrongs (usually stealing back things that innocent victims have been cheated out of), with the help and council of her friend Seira, who's also a nun in training who listens to people's stories. She tells the stories to Meimi, who turns to Saint Tail to settle the problem. But, although her objectives are good, to steal is a crime and Asuka Jr has dedicated himself to catching Saint Tail. But Meimi/Saint Tail likes Asuka, and this complicates matters a bit.