Dave is blissfully unaware that Karkat went the full asshole and started murdering innocent people. Honestly, the time difference did a number on their friendship. He remembers being best friends, Karkat remembers hating him. He'd felt too awkward to really try bridge the gap.

"It's no big. I'll laugh at his sorry ass when we get back to the Capitol." There's the barest hint of uncertainty in his voice at that, like he isn't sure it'll happen. "Please, I don't touch the stuff. If I want to take the edge off I'll stand up really fast." He rolls his eyes, pulling back just a little. "So am I." He says with more certainty. "Just don't let it get infected because like hell I'll ever amputate it."