Kurt froze and every inch of him stiffened. Someone was there and he didn't bother looking over his shoulder to find out who. Admittedly, he could have teleported away but he didn't. The cat ran off though with a soft hiss. Maybe it didn't like invisible people either. "Er, it's a fast food place where I'm from," he made himself keep the answer simple though his natural instinct was to keep talking.
Very slowly, he pivoted on his oddly shaped feet to look in the general direction the voice had come from. He was ready to run if need be. Or climb down the side of the tower. Whichever ended up being easier. "You had it the first time. I'm a mutant," the German boy answered carefully, knowing that could be a death sentence. "I'm called," he paused quite obviously, deciding that giving an invisible person his real name was probably a bad idea, "Nightcrawler."