provokers.... e.g.passive aggressive pics on social networking sites....the defence is 'humour'....the REAL purpose is to leave the recipient confused/unnerved/disappointed/upset but it's hard to challenge because it's disguised as humour.
Are you nice? Mean people do upset me, though. Mostly people who take advantage of others and are inhumane. Inconsiderate and stuck up people (people who believe that they are superior to others) can be pretty annoying too.