Book 2 of Legacy of Dragons. Spoilers ahead for book 1, and of course, for Pillars of Reality.
Kira and Jason enjoy a friendly sparring match in the opening, but it soon turns to disturbing visions of Kira that Mages have seen, and the way Prince Maxim presses to marry Kira.
They decide to try to convince the Empire by having Jason and Kira feign in public that they are so madly in love with each other that they can barely wait until they are of age to marry. At one party they attend, Kira sees someone who happens to look very like her. Somewhat thereafter, she's kidnapped and borne off on shipboard. Her parents and Jason get news that Kira left the city some time after the ship sailed. . . .
It subsequently includes Imperial conflict over the emperor's heir; Jason's remembering a tactic from a game; eating raw fish; Kira's claiming to be really, really hungry; counting ammunition; Mari's giving orders as the daughter; Alain's clearing his throat to insist on something; Jason's appearing in rumors as a demon, and Kira as the "daughter of darkness", and more