What Did You Do? by Jeneane O'Riley

Love that won't die
Vengeance to be wrought
Three families forever changed
Finally reunited with her family in the Seelie Realm, Caly struggles to come to terms with allshe had to give up to get there. Though she eagerly awaits the ceremony to receive the second half of her heart and become whole, it comes at an unsettling cost: She must marry her longtime friend Prince Aurelius to solidify her place within the Seelie Court.
But as the event draws nearer, she's haunted by the memory of Malum Mendax, the Unseelie Prince - the bond they shared in his realm, and the sinful sparks between them. She still feels his eyes on her, finds him in her bedin her dreams. . .and soon, she realizes it's more than just his memory that haunts her.
Mendax survived Caly's assassination attempt, and he has returned to punish his pet and the ones that took her from him.
With his return, Caly's place in Seelie is at risk.
Her future plans are at risk.
Her very life is at risk.
But the way Mendax makes her feel tempts her to forget it all just for the chance to touch him once again.