Following a strange dream, Yuko Yoshida wakes up to find she has grown demon horns and a tail. Her mother Seiko reveals that their family are the descendants of a dark clan who live in poverty because of the opposing light clan, stating that it is Yuko's mission to defeat a magical girl to restore the clan's glory. On her way to school that day, Yuko is saved from an oncoming truck by the very magical girl she is tasked with defeating. The next day, Yuko discovers that the magical girl in question, Momo Chiyoda, is a student at her school, leading to an unsuccessful attempt at defeating her.