Kathy (USA: CA) (2010/07/12): Book 2 of 6: Lexi, a werewolf bounty hunter is in the middle of an altercation with a 'skip' (person who skips bail) when Darius, an Immortal, literally appears out of thin air because of 'The Calling' (where humans Call Immortals for help).
The same demon from book 1 is trying to take over the world and it looks like you will have to read all 6 books to find out how the demon gets vanquished.