A 'dirty Natan' is when a male begins to start explaining British coins, what each element on the periodic table is used in or what sound each different part of the drumkit does, while raw-dogging a woman in the ass and then proceeding to make the woman moan in polish before finishing in the toilet.
Hey Kian, did you hear about what James did the other day? He pulled a dirty natan apprantly!
A Dirty Natanya is someone who doesn't want to steal your man/woman but ends up doing it anyway because her booty is just that thiccc all the guys and girls cant resist it.
Boys who enjoy yaoi (a genre in Japan that contains sexual and/or romantic relations between two men); literally translates to "rotten boy"; corresponding female : fujoshi