Sarah Mallory 
His Countess for a Week [EPUB ebook] 

A widow’s ruse attracts a dashing earl to help her find a killer in this mysterious historical romance.To uncover a ruthless killer, Arabella Roffey masquerades as the Countess of Westray, not expecting her "husband" to suddenly appear! He could expose her but instead agrees to continue her ruse for a week. Randolph is brooding, handsome, and Bella likes him more than she should. As she pretends to be his wife, they share everything except a bed-but the temptation to do so is becoming all too real . . .