The Shores of Solace is a beach house owned by Lord Cassius. This is one of the many "escapes" Lord Cassius uses when he wants to get away from his rocky relationships with his wife and son. During Nightfall, he asked Keefe to move in with him as part of a deal for information about the original Nightfall's location. Keefe agreed, despite Sophie's concerns, and now resides there with Lord Cassius and his ogre bodyguard Ro. Ro refers to it as the "Waves of Wimpiness."
In book 6: Nightfall, hardcover, on page 775, the Shores of Solace is called the Shores of Solitude.