I tried to make some eleborate scenario from the post game (when you choose a character to be your interlocutor from the main menu) without real success. Adding/Removing characters get the AI lost in no time (you can even get a notification into the game the character you 'speak' with would like to join you, but it is already there, so half of the screen goes empty) . Loading a save doesn't make the AI learn back what happened before the save, ...
The game is fine if you wan't random short interactions. But nothing more at this point.