By the way, in the otherwise completely unremarkable hobby-writer webnovel "Monroe" (https://www.royalroad.com/fiction/35398/monroe) the queen was a - very popular - side character. After the introduction of "magic" in our universe she got her youth back and started killing monsters using armor and huge sword used by her ancestors hundreds of years earlier, in a sword and magic and levels fantasy universe. The author kept writing chapters about this initially not very important side character after it turned out a lot of readers found the Queen returning to youth and becoming a sword fighting and magic throwing monster killer at least as if not more appealing than following the story's actual main character.
A list, British Kings & Queens - by Length of Reign: https://britroyals.com/reigned.asp
These two women take the two top spots.
By the way, in the otherwise completely unremarkable hobby-writer webnovel "Monroe" (https://www.royalroad.com/fiction/35398/monroe) the queen was a - very popular - side character. After the introduction of "magic" in our universe she got her youth back and started killing monsters using armor and huge sword used by her ancestors hundreds of years earlier, in a sword and magic and levels fantasy universe. The author kept writing chapters about this initially not very important side character after it turned out a lot of readers found the Queen returning to youth and becoming a sword fighting and magic throwing monster killer at least as if not more appealing than following the story's actual main character.
Sample chapter where she appears (look for "queen", it's down the middle of this chapter): https://www.royalroad.com/fiction/35398/monroe/chapter/84715...