Sakura Kinomoto is your garden-variety ten-year-old fourth grader, until one day, she stumbles upon a mysterious book containing a set of cards. Unfortunately, she has little time to divine what the cards mean because she accidentally stirs up a magical gust of wind and unintentionally scatters the cards all over the world. Suddenly awakened from the book, the Beast of the Seal, Keroberos (nicknamed Kero-chan), tells Sakura that she has released the mystical Clow Cards created by the sorcerer Clow Reed.