The Prince and the Dressmaker by Jen Wang

Prince Sebastian has a secret life. By day he is Prince Sebastian, heir to the throne of Brussels.  At night, he lives a secret life as Lady Crystallia, a Paris fashion icon!  Sebastian hires Frances to be his dressmaker and keep his secret.  Their friendship develops, and Frances’s skill as a designer is noticed by the fashion world.  How long will Frances be willing to put her dreams of becoming a famous fashion designer on hold to protect Sebastian’s secret?