She's backing off. Did that mean it worked? Was she calling his bluff? Strange's mind is working overtime as he thinks of what to do next. If the demon leaves the Circle alone for long enough, then he'll be able to do the proper research and cast the proper divinations to find out how to destroy her utterly and she won't see it coming.

"There will always be people who don't listen to orders. But I shall issue an order requesting that you be left alone." It's just that said order won't have any weight behind it. So he's not technically lying through his teeth, just mostly. There's a pause before Strange admits, "Really though, if any of the neophytes are dumb enough to attempt to bind you in the first place, they probably have it coming."

Kids these days with their fidget spinners and their Pokemon Go and their not properly preparing rituals before attempting to bind a demon to their will.