Definitionally, yes an object (or body part)... but also, more specifically, an object, without which, you can't get excited or can't have an orgasm. It's the difference between wanting and needing.

Also... hair pulling, if necessary for the puller, might well be a hair fetish. Read enough and you will find stories of people who are totally turned on by long hair, want to entwine themselves, or comb it and then use it to masturbate... again, it all devolves to want v. need and what you can (or can't) manage without it.