For a girl - Someone that has a huge sense of humour, large amount of friends (some she doesn't like or just often insults them) and a hot piece of ass ;)
For a guy - A total babe. Has lots of sex, younger sister is most likely to disapprove.
Morghse girl: My brother has sex like every week, you freaking whore.
Morghese guy: Hey.
some girl: what a babe