Tabitha by Stacey Brutger

What do you get when a domineering soldier, a protective stalker, an obsessive psychopath, and a snarky tech wizard clash with a quirky, socially inept assassin? The perfect mission!

Mercenaries have taken over a small town, and it’s my job to stop them by whatever means necessary.
Trained as a killer my whole life, I don’t know how to deal with the living. I prefer working alone, lurking in the shadows as I stalk my prey. My solitary existence comes crashing down when I’m ordered to join forces with four very sexy, infuriating men to complete my assignment.
I work with machines and logic rather than people for a reason. I’d rather kill a person than try to decipher their emotions. Feelings are a weakness, but Bast, River, Gage, and Pierce are determined to prove otherwise, and they just might succeed…if I don’t end up murdering the overprotective idiots first.

Things get complicated when they realize I’m not there to help them bring the mercenaries to justice, but an assassin sent to eliminate the problem. I’ve never failed a mission, and I’m not going to start now.