You have to do something or it will never end. These guys don't have special powers, they can't read you, they try this sh*t on everybody. If you pay close attention most guys will joke back with them, subtly putting them back in their place. You can do this, you can stare, look away, and shake your head as you walk away. You can talk sh*t and laugh at them with other employees, because these guys definitely have enemies. Or you can kick them in the balls and punch them in the stomach. Just do something, don't sit and take it.