Grasp

Zoo vet Blane Winters' grumpy attitude and muscles hide a romantic heart. He only relaxes when he's around animals, since he likes them more than people. He has some friends, a good job, and a place of his own, and he's sure that's all he needs. Until he meets a certain incessantly cheerful artist.

Studying meerkats as he paints a wedding present for his sister gives Falcon Harper the perfect excuse to creep on the hot vet. It takes his mind off the dreaded event: he’s happy for his sister, but his secret ex will be at the wedding... Spencer, who broke his heart years ago.
The solution is obvious: Blane can be Falcon's plus-one and show Spencer that Falcon’s moved on to bigger, better things all these years later. But feelings grow as Falcon coaxes Blane out of his shell. Just as happiness seems within their grasp, jealousy threatens to tear it away for good.