THE RENFIELD SYNDROME by J.A. Saare

Vampires, and werewolves, and demons, oh my.

Rhiannon thought facing off against a deranged child vampire was the most dangerous task she would ever have to undertake, but she's about to discover making a deal with a demon is far, far worse. Sent forward into another reality, one in which vampires are now dominating nearly extinct humans, she realizes the sooner she returns to her vampire lover, Disco, the better.

Unfortunately, time changes a lot of things, including those most trusted...