End of Night (Shadow Security, Book Four). Shadow Security, #4

Tiger shifter, Boone Jameson, isn't interested in love, not when grief rules his life. Until he meets Hedra Miller, the private nurse he hires to care for his ailing grandmother. His instant attraction to the sassy and gorgeous human isn't surprising, but his urge to be her mate is. Hedra's ability to extinguish his sorrow has him eager to spend time with her in and out of the bedroom. Too bad Hedra has a strict rule against sleeping with the boss.
Hedra's no stranger to mistakes. And sleeping with Boone would be more than a mistake, it could cost her everything. Unfortunately, ignoring her attraction to Boone proves impossible, especially when she's a live-in nurse. Not sleeping with the sexy tiger shifter requires a level of willpower she doesn't possess. As Hedra and Boone grow closer, Boone's grief and Hedra's enemies threaten to tear apart their blossoming love.
But when Hedra's life is in peril, Boone and his tiger will stop at nothing to save their mate. Please note this is book four in the series but can be read as a stand alone. This book contains steamy scenes that may not be your cup of tea.