I loved this bit of linguistic worldbuilding on pronouns from Rachel Hartman’s Shadow Scale:
Abdo gave me the expected fish-eye, but for an unexpected reason: Wrong gender. You use cosmic neuter for a stranger.
I glanced at Rodya; he leaned to one side and spat on the ground. He’s not a stranger anymore. If ever anyone embodied naive masculine, surely Rodya—
You use cosmic neuter for a stranger, Abdo insisted. And he’s a stranger until you’ve asked “How may I pronoun you?”
But you told me cosmic neuter was the gender of gods and eggplant, I protested, unsure why I was arguing with a native speaker about his own language.
People may choose it, said Abdo. But it’s polite for strangers. You may be almost sure he’s not an eggplant, but he might still be some agent of the gods.