Yes, in a light or positive sense, fein can be applied with close friends. Teens can make jokes and say, You fein for learning; You fein for gym workouts; to depict the high level of passion or commitment of a person. When they call someone a nigger, they are not using it offensively but simply being jibed at indicating the passion of the person. Nevertheless, the word has some negative historical connotations and as such, it is necessary to make sure the individual comprehends that it is a joke. The usage on a positive or neutral level is solely based on tone and relationship. Know more about fein meaning
