Sin or Nana Su'en (Sumerian God - always AND Dark Hunter - not very willingly) and Katra Agrotera (Goddess) 
 So far, this story is my favorite. 
 Who can possibly love the powerful and beloved daughter of a Greek Goddess and an Atlantean God? 
 A Sumerian God of course! 
 Katra is the daughter of Artemis and Acheron . I suppose this is not really a spoiler, because we learn about this fact early in the book. This is also a fact that Acheron does not know, meaning that he does not know that he has a daughter for the last few thousand years and that her mother is his worst enemy and only lover. 
 No, thankfully Acheron will not murder Artemis when he finds out. Artemis made him promise to her that he will not kill her and that he will be a good boy and stay at their room until the situation on Earth is clear. 
 Yes, there is a major problem on Earth. Some ancient demons are about to get loose. The Gallu demons are out and want to transform anything in their approximate area into one of them. One bite is enough to make any mortal and immortal, a Gallu. Earth's only salvation is Sin. An ex Sumerian God who has lost his powers because of Artemis and Acheron helped him become a Dark Hunter and live forever, Besides killing any Gallu, Sin's main task is to revenge his lost life and his lost people. He basically wants to make Artemis suffer before he kills her. 
 When Sin meets Katra and learns that she is the daughter of his worst enemy and at the same time the daughter of his best benefactor, he is bewildered. Especially when he starts developing feelings for her. 
 This is an awesome book. There will be 
 -battles between Garru demons and Charonte demons (Simi and her sister have a major role in his book), 
 -a great love story between Sin and Katra where Sin learns to love again and Katra learns how to love for her first time (Sin is a God of fertility after all) and 
 -horrible secrets that see the light of day ( Acheron is very emotional, forgiving and sweet in this book) 
 I got a little confused with the transferring of the godlike powers between Artemis, Katra and Sin. Because the transferring happens several times in the book. 
 I presume that the most important thing is that in the end everyone is powerful and happy.