Well ive been kinda wondering this because it seems that different areas seem to hurt more when you pull hair off them. And before you post please no talking about ripping your "genital hair" out.
I'm going to have to say armpit hair. My friend sneaked up on me with a pair of tweesers and yanked one out ...OWWWWW that hurt.
The actual hair on your head because if you've seen saw 4 you should know. Or maybe nose hairs cause when you pull it out, your eyes water and it hurts, A LOT!.
I've got hobbit feets!! Proud Feet! Ok, nose hair hurts! But if you pluck it enough, it doesn't hurt anymore. I guess the nerves die. I pluck my nose hair all the time, because I'm too lazy to get one of those shavers. Knee hair hurts too!
I have never tried nose hair, I can't get my finger in there far enough. :P Seriously, the hair that just reaches your neck really hurts more than anywhere else.