Negro is a word in Spanish, you, half brain, just insulted all Spanish speaker just to make yourself feel good.
Because burger are retarded and think that using a color is bad, when they dont have any issue calling these people black, dont mean you are right.
Antes de todo, creo que vale la pena informar que yo también hablo Español. Ni se me ocurrió la palabra "negro" mientras leía, así que tú argumento ya no se aplica.
In any case, let's not play stupid. It's already well known how quite a few manga/anime fans are also fond of twitter and the Chans (4chan is a homage to the very Japanese 2chan), and that the word in question is thrown around in these spaces with a very, very clear aim.
You seem to be already aware that your joke touches on a sensitive subject, which is a good thing and shows you have some good sense.
TL;DR: there's a reason 4chan thought and lingo stays in 4chan. I hope we keep it that way