Repeat Freebie (free multiple countries on Kobo but restricted on Amazon)
A Feral Darkness by Doranna Durgin.
Originally published by Baen now republished by the author.
I own this and enjoyed it.
https://store.kobobooks.com/en-us/eb...feral-darkness
http://www.amazon.com/Feral-Darkness.../dp/B003YJEWVC
As a child, dog-loving Brenna Fallon naívely invokes an ancient Celtic deity to save her beloved hound--and inadvertently anchors the new-found power at a spring on her family's farm.
She doesn't know she's also left an opening for a far more malevolent force.
Years later, thanks to the actions of several angry young men, Brenna discovers the terrible potential of that gateway. With a devastating plague unfolding abruptly around her, she must depend on her wits, a stranger she doesn't trust, and a mysterious stray dog who becomes more than just a faithful companion as she struggles to drive back the threat of a modern Black Death.
Welded by a desperate sacrifice, woman, man, and dog face the feral darkness together.