Cat Ommanney -- Real Housewives of D.C. star and Prince Harry smoocher -- says people don't recognize her until she moves her lips.

"It's only when I open my mouth I get recognized," the UK native said Thursday evening.

But since her new book, "Inbox Full," hits shelves March 3 (featuring her happy mug on the cover), people might start spotting this Washington sex kitten a bit more often.

Until then -- if she'd like some peace -- maybe she should keep her lips sealed, and off of royal mouths.

Sorry. It's like this, Cat.

• Download an excerpt from Cat's new book now