Gear Person #1

Gear Person #1 belongs to a race of sentient gears, one face in an alien crowd Rick and Morty stumble into on some far-flung stop in their travels. Like most background aliens in this universe, she exists mainly to make the setting feel stranger and more populated than the plot strictly requires.

The joke is the concept itself: a whole species built from interlocking gears, treated with total deadpan by the show's design team. Spencer Grammer, better known as Summer, lending her voice to a one-off oddity is the kind of small stunt-casting flourish that rewards attentive fans without asking anything of the story.