When Ella first meets Hattie, she can't help but notice her large front teeth. So does Char, who writes in his journal: "I don't know how she managed to pour the words out while smiling so hard, revealing the largest teeth I've ever seen. She must be excellent at cracking nuts" (22.50).
Not very charming, Char. And he takes back his words as unkind—even though they sure sound accurate.
Hattie's teeth lead Ella to mentally label Hattie a "rabbit queen" when Hattie confesses, under the influence of bogweed, that what she wants most in the world is to be queen (11.30-31). But oh, what a queen Hattie would make: she's jealous of Ella for being brave, she's afraid of every creepy crawly thing out there, and she seems to have absolutely zero empathy.
One of the reason's for Hattie's insecurity is that she keeps her wig-wearing habit a secret. (Luxuriant tresses must be the trend in Kyrria. We bet Thoréal). It's such a big deal that Hattie hides in her room when Ella steals her wig, at least until the replacement arrives (16.29). So we can add vanity to the list of Hattie's ever-so-charming traits—although, to be honest, we bet most teenage girls feel this way. Hey, most people probably feel this way. That's why they invented Rogaine.
Hattie definitely qualifies as a wicked stepsister: she orders Ella around all the time with no regard for Ella's health or feelings. But she's also a not-so-nice sister. Olive constantly feels that she gets less attention and fewer material goods than Hattie, whether it's fewer trunks of clothing (7.45) or the fact that Hattie doesn't let Olive try on Ella's necklace, leading Olive to complain, "Don't be so mean, Hattie." (7.90)
So, why is Hattie like this? Well, she seems to want control. By ordering Ella (and Olive) around, Hattie proves to herself that she's the boss lady of the situation. For example, at a dinner party, Hattie orders Ella in to tend the first in a "greasy, sooty state" (23.91), specifically to humiliate her. We bet Hattie enjoyed every moment of lording (ladying?) it over Ella while she was publicly humiliated.
And there's one more thing. Hattie's a liar. A big, fat liar.
For example, she writes to her mother when Ella runs away from finishing school (with Hattie's wig): "I suspect my locks have vanished with Ella. A hartless [sic] prank to play on me, who always treated her with kindness" (16.29). Yeah, with the same kindness as a shoe squishing a snail.
Want some more? She also lies about the glass slipper belonging to her, which obviously it doesn't, as her feet are too large.
Even more perplexingly, when Ella visits the masked balls as "Lela," Hattie pulls her aside to interrogate her because Char seems so interested in the masked stranger. Hattie claims that it's all from concern over Char, and then says: "You see, Charmont and I have an understanding. We are secretly engaged." (28.56) We're entering "dangerous lie" territory, because if Char found out that Hattie had said that? Whoa dude.
We don't know what Hattie was thinking with that last lie in particular, like whether she'd actually managed to convince herself that Char was into her. But ultimately, she's a really conniving character, willing to bend the truth to get what she wants.
We'd never play a game of Truth or Dare with her. Ever.