What do you call 2 black people having sex? Fucking niggers.
I'm a bit upset that you would tell a joke this offensive. Can you explain what you mean by it?
It means a sexual act between two black people which by definition is a nigger.
When people use racial slurs like that one, it encourages racism and perpetuates hatred toward black people. That word has a very serious history and is not something that should be used.