An annoying one is a person who is irritating and causes distress. The term can be used to describe someone who is a TWERP, TEASE, PEST, PAIN, or vexer. A TWERP is someone who is silly or foolish. A TEASE is someone who provokes or annoys another person. A PEST is someone who is a nuisance or bothersome. A PAIN is someone who is difficult to deal with or is a source of trouble. A vexer is someone who causes distress or annoyance.