I've had a few female friends allow me to feel their arm hair in the past. One thought her dirty blond arm hair was gross (I wanted to tell her it wasn't, but...), another hadn't shaved her brown hair since middle school (she was 20), and another finds no point in shaving her black arm hair.
And my current partner for one of my lab classes has light brown-ish arm hair. It gets....interesting how frequently her arms come within centimeters of my eyes in class.