I'm confused on how Ari works, sometime she'll just stare at me for way too long, then the next time she appears, she beats me with a broom. I don't understand how she work.
While Ari is in the doorway she blocks any other girl from using that door, blocks you from closing that door (even forcefully opening it if it was closed before she appeared there), and dramatically reduces your sanity drain from all sources. She’ll stay there as long as she feels like it and there’s no way to reduce that time as far as I know. If you look at her for too much of the time while she’s there, she’ll kill you once her time is up. So you need to look at your cameras to avoid looking at her and appear to be “working”.