Terezi had that one right on the nose. Karkat's still sore over the Dave thing, especially since their fight.

"I don't fucking know," Karkat snaps back, still moving. "She's usually on the rooftops or out looking for me."

He draws to a halt, trying not to wince at the way his side's throbbing. It wasn't that long ago that Tavros and Masaru punched holes in him, and all this running isn't helping matters. "It's not like her to just disappear like that, dammit! She should have contacted me by now, I mean what the hell is she thinking? We're given these stupid pads for exactly this kind of situation, it wouldn't kill her to at least let me know where the hell she is!"

Karkat's angry ranting isn't doing much to hide his worry. Or keep them from being noticed by the approaching horde.