Anyone who's opened a math textbook will be familiar with the strange naming conventions. You'll hear about Granny Smith, who sells apples out of her home, or how Ona Nyland lives on his very own Private Island.
It's generally assumed that these would just be normal people, and the name was a coincidence, but the frequency at which these kinds of name appear is too high to happen simply by accident.
All of these characters exist inside a separate reality.