Risa Humvee holds the position of Student Council Treasurer at Rikkyoin Academy. An American citizen, she speaks with a distinct Kansai dialect that colors her linguistic presence at the school. Her good-hearted, sociable, and cheerful nature makes her approachable to students and staff.

Her loyalty to Student Council President Ritsuko Kübel Kettenkrad is notably unwavering, rooted in Ritsuko's consistent respect and trust during a time when few others offered Risa such consideration; Ritsuko's reliance solidified her steadfast devotion.

As treasurer, she handles financial calculations with precision despite her seemingly rough exterior. Rumors hint at conflicting financial circumstances: she maintains an impoverished lifestyle, yet unverified accounts mention entries reaching ten figures in her bank records.