Blessed

Old enemies cast long shadows.
Meri's a necromancer hunter possessed by a necromancer's soul-and it's killing her.
Born with the ability to slow time around her, Meri left the fame and fortune of the gladiator arena behind to become a monster hunter for hire. Along with Gallmau, an exiled prince as strong as she is fast, she's traveled the world getting paid to fight animals and humans cursed with death magic. But the first necromancer whose head she took lurks as a parasite in her spine, and she's at the end of the three year's grace before he ends her life.
When the royal sorcerer summons Gallmau home, they travel there to offer their help-and see if he can lift her curse. Instead, they barely survive a fight with Sinan-an infamous death witch known as the Prince of Shadows-and arrive to find the royal sorcerer dead. Worse yet, Gallmau's sister, the heir to the throne, has been abducted, and they have no chance of rescuing her without Sinan's help.
The only thing more unsettling than working with a necromancer is Meri and Gallmau's growing attraction to him. Meri tries to hide her secret, fearing Sinan will help the undead necromancer inside her, and ends up putting all three of their lives in danger. When everything Meri knows about necromancers is upended, she'll have to face ghosts from her past and enemies from her present to save not only the princess but everyone she loves-both the living and the dead.

Prince of Shadows is the first book in a new MMF romantasy series, and features enemies to lovers, court intrigue, and a rather disobedient undead rat.