Her lips are devil red
And her skin's the color of mocha
She will wear you out
Livin' la vida loca
A common way to make a description of a person's skin colour more interesting and appreciative of a wide range of shades is to compare it to types of coffee. It's particularly common amongst descriptions of South Americans for two reasons. First, South America has a variety of skins tone often coming from the blending of several races such as native tribes, hispanics and the descendants of African slaves and the tones that occur tend to fit better. Second, South America is the origin of coffee and chocolate and so in some cases it could be a reference to heritage or particularly a mixed heritage if referring to a mixed coffee drink like a Mocha.