I own this library

This weekend I finally had to ban one of our regulars from the library, not for one egregious incident but for a bunch of little things that just weren't getting better despite constant warnings from staff and one-day 'bans.' I felt kind of bad going to do it because she definitely has something aytpical going on mentally, and I don't know how much she really understands what we're saying to her. Here's how the conversation went:
Security guard: So you need to leave this library, and you won't be allowed to come back here for three months. Do you understand?
Patron: I'll be back next week.
Security guard: What?...But, the manager and I will be here and we will know you are not allowed.
Patron: Oh, you won't be here anymore. I own this library, and I will replace you. I just need a week to bring on some new people.

After we escorted her out, I found that she had glued a bunch of random objects to one of our wooden tables with a huge glob of super glue, so I didn't end up feeling too bad for her.