Something does not have to exist in order for it to be discussed. There only needs to be a word or sign for it for a discussion to occur.
For example, in math, 0, ∞, √-1. In fiction, Winston Smith, Harry Potter, Golem. In mythology, Icarus, the Rainbow Serpent, Zeus. In religion, Amida Buddha, Susa-no-o-mikoto, Ahura Mazda.
All of these “things” do not exist. Language is a powerful tool. And language is also a great deceiver.
The difference between a sign and an existent thing needs to be clearly understood. An object motivates the concept, and in turn the concept motivates the signifier.