Richelle Mead: Georgina Kincaid series
Who likes light literature? After all, you can't always read War and Peace by Tolstoy. I have always liked this series, and it was one of the first series of novels I read in English and not in translation. I can't say that it was always excellent. There were some ups and downs in the story. But even so, I can only recommend it.
The protagonist is Georgina, who has a contract with the devil himself. Yes, in this world vampires and succubi serve the darker side of the Christian pantheon. There are also many divine beings in the story, along with dark wizards and demons, not to mention the alcoholic archangels. But the center of the story is a bookworm succubus who is trying to make the right decision. Especially when it comes to men. Not that she often succeeds. Neither of us can say that we often make good judgments when it comes to our love interests.