UBSB stands for ultimate back stabbing bitch
Someone who doesn't mind bringing others down to reach where they have to be.
Some random chick: woah who does that thing think they are.
Sarah: oh that's a UBSB you don't wanna mess with them they are dangerous.
R/C: a what?
Sarah: The Ultimate backstabbing bitch, you don't wanna mess with them they will do anything to reach to the top.
R/C: damn..
