I understand
The use of those terms among themselves, in rap songs and even among white friends is common.
A friend, white or black, can be muh dog or muh nigga. The situation dictates whether or not it is meant as affection or insult. It just doesn't work on the internet just like some jokes fall flat in cyber space wher mood, facial expression and body language is absent.
There was a brief discussion on OT awhile back regarding a tee shirt a black woman was wearing referring to herself as super nigger or somesuch.
When we strive to not offend it usually pays to err on the side of caution.
Thanks for you comments.