The story of Saint Tail follows a simple formula: school girl Meimi Haneoka transforms into the mysterious thief Saint Tail, and steals back what was stolen or taken dishonestly. She's assisted by a classmate and sister-in-training, Seira Mimori, whose position in the church after school each day allows her to hear the troubles of those who have been wronged and have come to pray to God. While Saint Tail steals to right the wrongs done to innocent people, she's a thief to the police force. Her classmate Daiki Asuka Jr., called Asuka Jr., and son of Detective Asuka, is hot on her trail. Saint Tail delivers notices of her planned capers to Asuka Jr., to give him a fair chance to catch her.