Romancing the West (Wild West #2)
Beth Ciotta

When the Peacemaker Alliance recruits lawman, Seth Wright, he's ready, willing, and able to kick ruthless desperado butt for the covert government agency. His enthusiasm wanes, however, when his first assignment takes him to California to propose marriage to Miss Emily McBride on behalf of his boss and deliver her back to Arizona Territory. He's a lawman, not a courier. Worse, the small-town librarian mistakes him for a dandified poet! Before he sets her straight, she confesses she's mixed up in something tawdry. With two unwanted suitors hounding her, the woman needs protection. So Seth assumes the fancy pants identity to room in her house without compromising her reputation.
Seth's good intentions take a monumental twist when he develops genuine feelings for the passionate book lover. She's not what she seems. More jolting, neither is he.