Harlequin Presents Readers discussion

The hero is a sheikh or a prince of a desert kingdom. The heroine is a foreigner who is attached to the kingdom and it's culture . She would have gotten the love for the kingdom from her grandfather who was probably an archaeologist. The heroine anonymously donates an important book to the kingdom. The hero calls the heroine back to write a caption or something for the book. He acts like he doesn't know who donated the book but knows it's her. The heroine struggles to accept that she is a native and thinks that she's an outsider to the kingdom. She wears a hijab and all. She tries to enter the kingdom conspicuously but the hero finds out about it.

This is most probably a harlequin book