The archetypical "kimagure" (whimsical) character, Madoka is secretly in love with Kyousuke, and is best friends with Hikaru Hiyama (who is also in love with Kyousuke). Madoka is described as having an adult allure despite being in junior high school.
When she first meets Kyousuke, she appears to be a pretty and sweet girl. This, however, is in stark contrast to her personality at school, where she is aloof and feared by both the male and female students as a reputed juvenile delinquent. In the TV series she is nicknamed "Madoka the Pick" due to her ability to wield a guitar pick like a shuriken. Despite her "punk" reputation, Madoka is also shown to excel at various activities both scholarly and athletic. She is able to earn high marks in school and still work a part time at Cafe ABCB (pronounced "ah-ba kah-ba").
Madoka's parents are kind-hearted but workaholic professional musicians often touring outside Japan, so she lives in a large house with her older sister. After her sister gets married and goes to live abroad with her husband, Madoka lives there alone. The story involves the eventual shedding of her tough exterior after she becomes Kyousuke's friend, as evidenced by the changes in her life after she meets him. She gives up smoking because of him, and in the manga other characters note that she becomes friendlier and does better academically following Kyousuke's arrival.
Creator Izumi Matsumoto reports that his inspiration for Madoka was actress Phoebe Cates.