A book where a normal girl is suddenly called to be royalty in like, a hidden kingdom.

[Lizzy]

I'm pretty sure this is in a series of books. I read it in middle school so, anywhere from 2015-2018 but it's probably around the middle of that. Anyways, this book is about a girl who's life is pretty normal until one day she's suddenly the princess/queen in a new land full of like, elves or fairies, maybe goblins. I'm not sure exactly but I'm pretty sure they're not human and instead are some kid of mystical creature. The only specific parts that I remember are two main scenes. One, where she's at a ball or something shortly after she's introduced to the kingdom, and has to dance with a chancellor or something, and she explains in detail how fat and sweaty he is. Another scene is where she sleeps with someone (he's like a guard or something I think.)I also think either he or her is supposed to be marrying someone else, and I'm pretty sure they end up dating for a lot of it at least I don't remember if they stay together.
I'm not sure if that's two vague or not. Oh, I'm also pretty sure there's different kingdoms. I'm remembering that they maybe visit an ice kingdom, or something like that.

[Margaux]

Did she have a love interest who was also from a powerful/royal family and his skin was kind of green? And the fairy/goblin/whatever queen who is her real mother placed her in a human family so she could steal inheritance?

[Lizzy]

hm, I'm not sure. what book are you thinking of?