All things considered, it's a very good thing that Katniss has such dark skin, otherwise the way that the blush creeps over her cheeks would be much more visible than it is. Which is ridiculous. She's not a prude. It's just Gwaine's casual mention that's thrown her for a loop, and she gives him a flustered scowl in return for it. "Well, now I don't want to ride it after all. Since you just made that reference."