Dagger by Delilah Devlin

Although a professional bounty hunter for nearly ten years, he’s the new guy on the block at Montana Bounty Hunters. As the new guy, he can’t catch a break. Reaper Stenberg still resents the hell out of him because he used to work at rival agency, and because he’s just that good, he scooped a couple of high dollar bounties from under Reaper’s nose. Brian, the office manager, is mad as hell at him for flirting with the pretty postwoman he’s crushing on. But Dagger doesn’t have to prove a thing to any of them.

All he has to do is earn his bounties, but then he’s assigned a partner–his former boss at that rival firm. The last thing he wants or needs is a partner, and certainly not Lacey, who managed to resist his charms in the past. When they have to go undercover at a couple’s retreat to take down their target, not everything’s an act. The old heat’s still there, if only he get Lacey to admit it…