Nick definitely didn't know there were any porters around. Really, he should have at lest assumed that there might be one, but he wasn't thinking that way since there wasn't anyone from his world around. But when someone was suddenly there, and momentarily covered in shimmery (thanks a lot, Cassie, for getting that word in his head at times) light, he couldn't help jumping. "Holy shit," he said as he jumped, eyes just a bit wide.
He watched her for a moment, and once she'd stopped shimmering, he added, "Uh, I didn't know there were any porters around here." Really, he could probably blame himself for that. He hadn't exactly been out making buddies with everyone, but that was just a habit he'd had since he was a kid. Especially since his dad was killed. The more friends you have, the easier the watchers can track you, or the sniffers can sniff you out, the more people who really know you, the more ways for you to be found.
Luckily, he didn't have to worry about that in Lawrence, it was just a force of habit.