Belinda Tower holds the position of games captain for the entire school during her fifth and sixth years at St. Clare's, becoming head girl in her sixth year. She possesses a notably hot temper, though her anger typically subsides after a time. Despite this intensity, she commands respect and is well-liked among the students.

Her personality blends impatience with moments of gentleness and soft-heartedness, particularly evident in her interactions with animals. She shares this fondness for animals with another student, Kathleen Gregory. Belinda communicates in an outspoken manner, a trait that intimidates some.

As sports captain, Belinda demonstrates fairness and leadership. She selects Patricia O'Sullivan for the lacrosse team after recognizing her athletic talent, despite Patricia having previously defied school rules and deceived Belinda regarding chore responsibilities. This decision follows Patricia's confession of dishonesty, showing Belinda's capacity to prioritize merit and honesty over past infractions. Her approach contributes to Patricia's developing sense of responsibility and respect for authority.

Belinda first appears in the narrative during the initial term of Patricia and Isabel O'Sullivan at St. Clare's. Enforcing school traditions, she assigns chores to younger students, including tasks like boot cleaning and toast preparation for seniors like herself. Her interactions with the new twins, particularly their initial resistance to these duties, form part of her supervisory role within the school hierarchy.