User blog comment:Zathronas/Analysis by an author: World of Remnant, Kingdoms/@comment-4909254-20140919025130/@comment-9090085-20140919171923

True, but just because a King hasn't been mentioned doesn't mean one doesn't exist; A comic I read called MÄR pulled exactly that trick - for most of the story the characters are trying to defeat the Queen and her head Knight, only for it to be revealed afterward that there is a King they need to defeat as well.

It's a little like the logic behind saying "if there is a Beta, there must be an Alpha". That's just what I think, though.