(So.... OOCly, I have no interest in being in a PVP here, but Banny meant what she said: we have no actual authority to be in the inn, we are trespassing, we have been asked to leave, and at this point we're actively damaging property, on pretty thin evidentiary grounds. Speaking ICLY, Banny would try and stop Alicia at this point.)
(That said, the converse is that Banny is not Alicia's parent and has no authority over her other than the dubious authority of being 'older than her' and the both of them working towards the same goal, and Alicia's consequences impacting Banny's goals. Sooo.... I can just have Banny leave with Jess before the knife digs in, and let Alicia deal with whatever the response from Cham is, if that's what you want. *shrug* Other than that, Banny would physically be trying to stop Alicia from doing this. Do you have a preference, Alicia?)
Ah, the first clash of alignments. ;P Ali definitely doesn't have the same motivations as Banny, or the same ideas about what constitutes acceptable behavior. She's not going to get into a fight over it if Banny tries to snatch the dagger away when she starts damaging property, but Cham definitely rubs her the wrong way. It doesn't bother me either way, whether Banny leaves before Ali starts chipping off paint or stays and tries to stop her.