Any regular ditzy (moronic) girl/woman who believes the world revolves around them due to the size of their breasts. They often use the size of their funbags to get ahead in life, due to the fact that they don't have an actual brain to speak of.
"Dude, why the fuck are we letting her lead us around? She's a complete ditz!"
"She may be a ditz, but she's a ditz with tits, and you can't argue with that."