Undying Devotion

Shannara is a hard-working detective called in on a serial killing case.
Not long into the case, things begin to take a turn for the worse.
With no other logical choice, she is forced to make a deal with a demon.
The deal is in exchange for her hand in marriage.
As the mystery unfolds with each death, will she be able to discern between genuine affection and a twisted desire?
Why does this demon want to marry her, and can she hold on to her only thread of sanity left as she loses herself between worlds?

The first installment in the Undying World of Demons!