Draco had heard someone coming - but these were the dungeons and he was a prefect, and it wasn't like he had anything to worry about from professors, not at the moment at least, not with his Mark matching theirs. So he hadn't hid, and when it turned out to be Nott, he relaxed almost completely. Nott was harmless, he'd come to believe, even if his Father was one of them. Nott rarely made sense enough for anyone to take him too seriously, even if he were to know something about why Draco was here - which he wouldn't.
"Nott," He said, leaning against the wall casually, his back against cold stone. "Out a bit late?"