When you find someone who could be your twin, except that they are black and you are white

A class of US citizen that receives all their news from the National Public Radio, or NPR, and no other sources. See: shit-lib, NPC, or SWPL (white educated liberal bohemian).

This personality is the counterpart of an American who is addicted to Fox News. Both demographics fail to cultivate objective opinions due to a biased media diet. This is to no fault of both groups; it's the result of the USA's piss-poor journalistic standards, ethics and values.

though you may act like a typical white kid around your white friends, your alter-negro is the way you act around your black friends.

Alter Negro is an alternate ego of an African American, typically for African Americans that have made success in such fields as: rap, hip hop, R&B, as well as other musical styles favored by mainstream listeners. Usually used in the comparing of artists' lifestyles before and after they become well known.

A black person who does not act like a typical black person. This person is usually always up to mosh and likes hardcore bands. Often referred to as white washed.
The name came up because the first people in punk rock were actually black. So they arnt black people turned white. They are another form of a black person.