Anvilicious: The first book makes it pretty obvious that, just because someone is beautiful, it doesn't mean they are necessarily good, as seen with Aunt Lily, who bewitched every member of the Bliss family through her beauty and charisma, but turned out to be evil and only wanted the "Booke" for herself.
The Heroine herself, Rose. Kids and preteen girls adore her and consider her a great and relatable protagonist. Outside of the Target Audience, she is despised for her serious self-esteem issues and is seen as annoying.
Lily Le Fey. Opinions whether she is a great or a weak villain, for her interactions with Rose, vary. Part of it has to do with the fact that it was obvious from her introduction that she meant no good and that she wanted the "Booke". As a result, many theorised that she would reveal herself at the end of the book, only for her to immediately leave and take the "Booke" with her, with no one noticing it.
Broken Base: There's a huge debate over the main cast of the series. Does it consist of relatable and well-meaning kids, or of four brats, whose flaws overtake them?
Evil Is Sexy: Aunt Lily is beautiful, exotic and a gifted cooker. She is everything a man would desire and more! Even Rose's brothers, Seige and Thyme, and eveb Chip had a crush on her. Until her true intentions were revealed
Seige, for all the problems he caused by showing the "Booke" to Aunt Lily, despite her sister's protects. He is even more hated than Rose!
Rose's love interest, Devine, for being a Satellite Love Interest, with little to no contribution to the main plot, and made Rose look like an obsessed stalker. Usually, characters like him manage to get away, but he was mentioned so frequently that many thought he would have a bigger role later in the book. Turns out he didn't.