What does it really mean to be a magical girl?

Madoka Kaname is an eighth-grader who leads a peaceful, fun-filled life as a student, surrounded by her beloved family and her best friends. One day, a transfer student named Homura Akemi arrives in Madoka's class. She is a dark-haired beauty with a somewhat mysterious disposition. Soon after meeting Madoka for the first time, Homura goes on to issue Madoka a strange warning. Madoka also meets Kyubey, a mysterious looking white creature. He says, ""Make a contract with me and become a magical girl!"" To make any wish come true – Madoka didn't know the meaning of this miracle nor what its cost may prove to be. An impending loss triggers a drastic change in her destiny...