Cassie's smartass grin fades as she catches his reaction. She likes teasing him when he's getting a little enjoyment out of it himself - she doesn't like touching a nerve.

"Sorry, I'll stop."

It's a good deal more sincere-sounding than the usual apologies she gives when she offends somebody. Unlike most of them, his opinion matters.

"But if you ever did want to call yourself a prince, you're definitely handsome and regal enough to pull it off."