"Ah", he expressed his understanding. The young man's obvious tone was making Natty feel a bit stupid, but he reminded himself that there was no particular reason why a Groundskeeper would be familiar with the rules of the library. "I only spent one year at Hogwarts, and now I'm mostly", he gestured vaguely out the window, "out in the Grounds. Do you have access to the Restricted Section then?"

If he didn't, that might explain why he wanted others to follow the rules too.