Diamond & Dawn (Amber & Dusk, Book Two)

Mirage has returned to Coeur d'Or, triumphant in battle, and ready to claim her rightful place as the Amber Empress, and resume her tentative romance with Sunder; but the city's people are afraid and not welcoming, somebody is trying to assassinate her, the previous empress, Severine, is in a coma and not as dead as Mirage would wish, and a distant cousin Gavin d'Ars has turned up with a rival claim to the throne--and in the turmoil all her alliances are beginning to fall apart.