Vix is about a human who is taken by a necromancer and a vampire. It's not a great jump in place, but I do consider it a stand alone novel. It happens at the same time as THATH and TWATN and is therefor also the "7th" book in the chronological timestamp.

By publish date it is the 6th book
By chronological date it is the 7th book

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Vix Hedgewood never thought vampires existed, much less necromancers and strange witches. In a world full of excitement and supernatural, Vix was a human.

Vix, stuck in a house with a WW2 vet who has a face of an angel and a heart of gold, and a necromancer who's too caught up in himself to do what's right, Vix is starting to grasp onto concepts she had never thought of before. Like the fact that half the world wants her dead for reasons she didn't even know.

Being kidnapped was terrible, beginning to love the henchmen of said kidnapper was worse. And learning all the secrets about her and who she really is? Well... that was the hardest.