Mary Sue: Alex. There are a lot of similarities between the author and her favorite character.
Canon Defilement: These stories are constantly breaking rules in order to make the plot work or just from lack of attention to detail. For example:
Instead of giving the elf King the proper title, Aganir, the author chose to use the incorrect title/name Nir. When reviewers brought this inconsistency up, the author gave a Hand Wave instead of fixing the mistake.
Trying to have Alice attempt suicide even though that goes against the rules of the universe and the purpose of the elf King's Wife protection spells.
Designated Villain: Eresha. Her main motivation in the series is to be close to her sister, who she raised while she herself was a child and who is is the last living relative she has after their parents died while they were young. Yet, she is treated like crap by everyone she crosses paths with, even the sister she loves and wants to be close to.