A novel with mature themes is not for kids because it is written from the perspective of adults. Lisa Kleypas has written for adults most of the time and she has used themes that are not for the kids to understand. So if you are not an adult then you need time before you would be able to understand the stories which the author puts on display.
Anna Parker-Naples was right on track while narrating this particular novel so no worries in that section. This is the tale in which everything is brought to light in slow motion. The author does not spread all the beans at once rather a lot of time is consumed before everything is put in front of us. A mysterious woman is introduced in the story who is more like the characters we observed in Marrying Winterborne.
The woman is awesomely beautiful and she is in serious trouble because of some unknown reasons. No one knows anything about her including her own self because she has a memory issue. She cannot remember who she is and why there are so many people determined to get rid of her as quickly as possible. Cold-Hearted Rake had that kind of urgency in it, the difference is that the enemy is operating from behind the shadows in this one.
Luckily the lady is provided with a hero in the story who is really interested in her case and he is completely focused to solve the case and save the girl eventually. For this, he has to dig deep into the past of this woman and risk his own life in order to save her from the dangers that are coming to her.