It's a nice smile. One Clara wishes she could remember if she's seen it or not. Though her gaze now lingers on him for a different reason. So Bucky went on a date with someone who looked like her?

Sure, Clara could absolutely see an echo of herself going out with a handsome guy like him. "Taking a girl to see a flying car on a date? Sounds exciting." Her tone of voice is genuine about liking that. "In my case, it's not just one doppleganger - more like thousands."