Wild Thing by Doranna Durgin
Mark Burton and Tayla Garrett are Sentinels, members of an ancient clan of shapeshifters who protect the earth and humanity. As part of the covert organization, Tayla and Mark had known each other for years...though neither of them recognized the deep desire they secretly harbored for one another.
Then Tayla and Mark are teamed up to work on the summit, a meeting with an informant from the Atrum Core, a ruthless group that uses their abilities to gain power at any cost. But Mark also has another assignment--to help a struggling Tayla meet her full potential. And the only way to get Tayla's powers to fully mature is by becoming her Sentinel bedmate....