Thotties are promiscuous females, sluts.
Often like to participate in drinking and doing drugs.
Most "Thotties" are often times young single mothers who live with their parents.
They are typically someones "plaything" and are tooted and booted very quickly.
Most men will not marry this type of female but will however spend a couple days partying with such and then move on.
As a result a "Thottie" will end up single again, looking for another dude to get "Turnup" with, or they will end up with a baby.
Term made popular by the sensation from Chicago known as Chief Keef.