Karkat's first response is an almost impulsive frown, but he doesn't miss that look. Worry is well-known in a place like this, something he's seen on many faces, and an expression he's worn quite often himself. For that he doesn't leave.

"It still hurts, dumbass. If you can keep alive longer, you have a bigger chance of winning and helping out your District. Or if you don't care about that--" He decides not to get into the Capitol and its politics. "--then maybe you can keep from looking like a chump who gets offed in the first week. But hey, why listen to the veteran? Just jump off the platform and blow yourself up at the start if you want to get it over that much."

It's not the gentlest way of putting it, but then she's not done much to encourage gentle. Bluntness might put the sense of it in her, he hopes.