Depending on what Karkat knows about Organization XIII - regardless of how he might know about them - the coat that this particular arrival to the Meadous is wearing is probably a little familiar. And if it isn't, well... people who willingly go about in black from head to toe aren't often the sort of people who mean well.

But since politeness will do best in a strange new place, he offers a nod to Karkat as he passes. It is, after all, the least he can do.