Oh boy another weird one which is a game-killer this time.
I loaded a saved game and headed for the market to look for a better bow (because the Oak Flat bow doesn't persist between saves). I decided to trigger the fish thief conversation with Scarlett. She argued in favour of the thief, Rod against. Scarlett won. a guard came running up, even before Robin stole the fish. Scarlett vouched for him, Rod denied it, Scarlett won again.
But Robin and the guard were still standing there. I couldn't talk to either one, nor the citizen standing nearby. I switched to Roderick (to sell things) talked to the nearby fish vendor, and something was bugged with her conversation: She commented sourly that she can't talk because she has to watch out for thieves. The first dialogue option was "Tell me about Cyseal", but there was some text behind that in brackets I couldn't make out, maybe something to do with (Continue...)?
I traded and walked off as Roderick. A few steps later, I realized that Scarlett wasn't following me, even though the chain was attached to the portraits. I walked back. She was still standing there. I switched to her and ended up with her in conversation with the vendor I just traded with, except now the vendor only has the "sorry I can't talk, watching for fish thieves" dialogue and I have no options to end the conversation. I'm stuck there and have to quit the game and reload. (At least I could still access the menu to go back to the main menu.)