Citizens reacting with alarm is something that, as technically a superhero, Karkat's supposed to react to, especially with all this time travel shit going on. He's kind of apprehensive about the idea of getting himself caught up in any of that – he feels like having to deal with any future Karkats is probably best avoided – but he figures he should at least check it out so he can call for backup or something, if he has to.

What he isn't expecting is that flare of familiar red and blue light.

He assumes it's just regular Sollux at first, and he's about to run forward to tell him to chill the fuck out before something happens when he realises that while it's definitely Sollux, it's not the one he's anticipating.

He hangs back, apprehensive and alarmed.