People with this name tend to get angry a lot, mostly out of their own selfishness. They are often egocentric and you are their enemy unless you have good things to say about them. Joanna is the name for someone with intense built up anger that get's taken out on people who doesn't deserve it.
Guy: So joanna, I heard you had started working out?
Joanna: WHO DID YOU HEAR THAT FROM? MAYBE YOU DIDNT! MAYBE YOU JUST ASSUMED I HAD BECAUSE YOU THINK IM FAT. YOU THINK IM FAT DONT YOU. YOURE A HORRIBLE DOUCHEBAG.