The Royal House of Illyria, Series by Robyn Donald

Seduced into submission! For Gabe Considine, Grand Duke of Illyria and a ruthless billionaire businessman, it's payback time! He believes his ex-fiancee, Sara Milton, stole a priceless family heirloom and betrayed him with another man. Now Gabe wants his pride -- and his property -- returned ! He'll lure Sara to his remote castle -- and keep her there until she gives him everything he wants, even if he has to seduce her into submission....

Princess Melissa Considine of Illyria is instantly captivated by billionaire Hawke Kennedy. She throws caution to the winds and lets Hawke teach her how to love... and be loved. But Melissa is virginal and innocent. How can she handle a man of the world like Hawke? And she's been brought up to put duty before love. But to leave Hawke's bed is to leave his life--what should she do?

The passionate prince-- When Prince Marco Considine sees model Jacoba Sinclair, he wants her-- The supercool supermodel-- But Jacoba can never surrender to Marco. She fears he'll discover her secret-- And a reason for a convenient marriage! When Jacoba's secret is uncovered, Marco seizes his opportunity. By announcing their engagement he can offer her royal protection--and royal passion!