We don't need to refer to a librarian that way. Yeah, I know, Seinfeld did it. It isn't funny or interesting. It is a cliché. Let's try to choose our language so that our history and language can hold onto meanings that matter.
There is a Star Trek TNG episode called Darmok that describes a culture that only speaks in metaphor. https://en.wikipedia.org/wiki/Darmok
Surely we have a better metaphor for a meek but powerful librarian than ...
> Who will be the library nazi that kicks you out when you talk too loudly?