oops forgot the picture 
Wow! I'm afraid I have no idea why this is happening or how to fix it. There's no way this could be due to a mistake on my part, I've never put those characters there in the first place, so there should be no way for them to show up. The game just seems to have gone crazy.
Does that bug always appear? Does it prevent you from continuing to play normally? If you leave and enter the map, is it fixed?