Hellfire and Brimstone by Angela Roquet is the 7th and final book in the Lana Harvey Reapers Inc. series. First of all, if you aren't familiar with the series, I highly recommend that you begin with Graveyard Shift. It is the first book in this series and it's free. Everywhere. All the time.
This series follows Lana Harvey, a reaper, and chronicles her (after) life in the well, afterlife. The world building and character development is great from Book 1. But by this installment (Book 7), the author is really nailing it.
One thing I love about this series is the relationships between the characters. Lane is at the center of a web of "chosen" family, and there are plenty of opportunities for them to prove their love and loyalty, as a war/rebellion/revolution unfolds in the series. My favorite relationships are between Lana and a western-movie-lovin' Gabriel and her romantic love with Bub, aka The Prince of Darkness.
I don't like reviews that give spoilers, so I won't do that to you here. But I will say that this book (and this series) gets an A++ for character and world building, as well as sexiness.
If you're looking for a quick, enjoyable fantasy read with a dose of sexy, this one is for you.
Learn more about Ms. Roquet, this book and her other work here.