Mildred

Mildred is one of Futurama's passing faces, a small-role figure who drifts through New New York's crowded, wisecracking world without ever needing a spotlight. She appears, says her piece, and moves on, part of the show's dense background hum of eccentrics rather than a character built for a long arc.

Tress MacNeille built a career on exactly this kind of role, giving throwaway characters a distinct voice and comic snap that makes them land even in a single scene. Mildred works because Futurama trusts its margins as much as its leads, and MacNeille's instinct for timing makes the smallest line memorable.