Mayumi Saegusa is a fictional character from the light novel series The Irregular at Magic High School, created by Tsutomu Satou. She is a talented magician and a student at First High School, known for her strong leadership skills and determination. Mayumi is the student council president and plays a significant role in the story, often showcasing her abilities in various magical competitions. In the series, Mayumi is characterized by her intelligence and strategic thinking. She comes from a prestigious family, which adds to her reputation within the magical community. Her relationships with other characters, including Tatsuya Shiba, are central to the plot, highlighting themes of friendship and rivalry.