Meimi Haneoka is a mysterious girl thief pursued by the police... and her classmate, Asuka Jr.. Her intentions are pure, however. Meimi's best friend, Seira, listens to people's troubles, and then, sends Meimi out as Saint Tail to help them.
A girl's grandfather accidentally appraises a fake gemstone as the original. Saint Tail must switch the two gems. With Asuka Jr. on the scene, Meimi finds herself in more of a challenge than usual, but she overhears him defending her.
Will Asuka Jr. catch his thief... or will she steal his heart?
Chapter 2, Calling Card Challenge -
Meimi overhears Asuka Jr. bragging about his victory over Saint Tail. Seira drags her away before she can make too much of a scene. To prove she isn't scared of being caught by Asuka Jr., Meimi sends him a message announcing her next mission, getting a crown named The Electra back to it's rightful owner. Meimi meant it in good fun, but a rumor spreads that Saint Tail and Asuka Jr. are working together.
Seira guesses that the crook will attempt to catch Saint Tail by telling Asuka Jr the wrong hiding place for The Electra, so Meimi must steal in sucessfully to clear Asuka Jr.'s reputation. When she takes The Electra, the crook pulls out a gun to foil her escape. Asuka Jr. knocks him over, saving Saint Tail, but shouting out a challenge to her.