Sins of the Demon. Demon Novels, Book Four

Louisiana homicide detective Kara Gillian is doing her best to cope with everything that's happened to her over the past year, all while s continuing to hone her skills as a demon summoner. But lately she's beginning to wonder if there's a little too much demon in her world. She has a demon for a roommate, the demonic lord Rhyzkahl is still interested in her for reasons she can't fathom, and now someone in the demon realm is trying to summon her.
And there's no way that can end well. Meanwhile, people who've hurt Kara in the past are dropping dead. Kara is desperate to find the reasons for the deaths to clear her own name, but when she realizes there's an arcane pattern to the deaths, she knows that both the human and the demon worlds may be at risk unless she finds out who's behind it all. She's in a race against the clock and in a battle for her life that just may take her to hell and back.
Sins of the Demon is the exciting fourth installment of the Kara Gillian series.