The best girl ever! you will never meet anybody cooler or better than her! Baani's are usually good friends and don't have too many bad traits. They are kind and sometimes introverted. They are usually really chillpeople.
When you're so down bad that you need an extension of the phrase to define just exactly how down bad you are. This version of down bad doesn't always have to be applied sexually. It could mean you're down bad for a delightful date, or you're just doing shitty in life overall.
In other words, you're either doomed or desperate as hell.
Chad: "Bro, my girlfriend broke up with me AND I failed finals."
Brad: "Man. You down badarious, dude."