All About That Sass by Michele Bardsley

A vampire, an outcast werecougar, and human female created a love that will last forever … but their lives are at risk thanks to the machinations of those they left behind.

Dying human assassin Cyn Salais agrees to take out a powerful vampire’s ex-lover and his family in exchange for eternal life. But after she crosses the paths of two were-cougars near her target’s house, she finds herself clashing with the rough-and-tumble male shifters.
Aris and Kane, shifter soldiers of the Harper were-cougar colony, aren’t used to being taken off-guard much less getting their asses kicked. Now, they’re hot on the trail of the sexy woman whose skilled fighting has them both infuriated and intrigued.

When the two were-cougars catch up to Cyn, her dangerous moves and sassy damned attitude will leave them with one question: Do they kill her … or mate with her?