Madoka Kugimiya is a student in Class 2/3-A at Mahora Academy, holding seat number eleven. She was born on March 3, 1989, has blood type AB, and stands 160 centimeters tall with dark violet hair and green eyes. She is one of the three cheerleaders of the class, alongside Misa Kakizaki and Sakurako Shiina, and is regarded as the most serious and level-headed among them. Her role within the group is to keep the other two out of trouble, though she is not always successful. She enjoys gyudon from Matsuya, silver accessories, and Western music, with a noted interest in Avril Lavigne at one point, and she dislikes playboys. She is mildly self-conscious about her own husky voice. Her surname is frequently the target of teasing nicknames from her classmates, which she does not appreciate.

Madoka is protective of her friends, especially Ako Izumi, whom she actively encourages to become more confident. During the school festival, she develops a small crush on the teenage form of Kotaro, though this does not develop into a major storyline. She participates in the Mars vs. Mages event, where she is among the first to be hit by the robots strip beams. In the Suka incident, she transforms into a black panther. She is also a member of the band Finger Punch Rocket, playing the guitar. Her motivations center on maintaining order among her cheerleader friends and supporting those around her, particularly the more timid Ako. Over the course of the series, she shows modest personal growth in her willingness to push others to face their feelings, as seen when she pressures Ako to confess to Nagi, though her plan backfires when Ako only asks for his email address. Madoka does not possess any magical abilities and remains a normal human student throughout the story. Her role is primarily that of a supporting character who provides comic relief and a grounding presence among the more eccentric members of the class.