Introduction to the task of killing fish in the dream westward journey market?

To put it bluntly, I want you to go somewhere and kill a thief in the fish market. I didn't do much about this task, but I feel strange. I painted a bunch of fish market tasks with my vision of meat DF. It seems that the role of brushing down the fish market task is to raise prices quickly, which is useless. I basically don't do it until it brushes the price back by itself.