Opposite racism?

this pretty much. i still dont get why black people get offended so much when people of other race call them a nigga but okay when their own people call them a nigga. i mean i'm asian and i don't go around being offended when some people jokingly call me "chinky eyes" or any asian-related stereotypes name

Has to do with the whole when white people said it it was used as a derogatory terms for ages. As for other races using it it went mainstream since rap music did. I hardly see anyone black or otherwise using in any context just sorta lost any meaning it had when everyone started listening to rap and saying at the end of every single sentence.