Closer to the Chest: Book 3 by Mercedes Lackey
Herald Mags, the King of Valdemar's Herald Spy, has been developing a network of informants who observe the Court and the alleys alike, quietly gathering information to keep the Kingdom safe. Meanwhile, his wife Amily is growing into her position as the King's Own Herald, though she is irritated to encounter many who still consider her father to be the real King's Own. Nonetheless, she finds it increasingly useful to be underestimated, for there are dark things stirring in the shadows of Haven. Someone has discovered secrets of the women of the Court and the Collegia-and is using those secrets to terrorize them. They are targeting the religious houses of women, too, leaving behind destruction and obscene letters. Mags and Amily use both magic and wits to try and find the evildoer. But just as they appear to be on the verge of success, the letter writer tires of terror. Now they are out for blood...