Comes from the german word for no (nine)
nine can also be used in the place of niner
At first was used mainly by scros, but now almost everyone uses it.
Scro 2: Shob, Niner, i wish!
Person 1: hey do you have the latin homework?
Person 2: niner
Person 1: duuuuuuuuuude she is so HOT
Person 2: NIIIIIIIIIIIIIIINNNNNNNNNEEEEEEEE