for a guy it would have to be the part under there belly button to right above there wanker..hehe and lips definitley lips..
The iris.... it must be all those colors that keep myself mystified. ...and let's not forget the clit... "I am the clit master!!" hahaa...Jay & Silent Bob...
For guys... this may sound strange but I LOVE hips. I love when they protrude slightly (not in a muscular way, but in a skinny way). For non-sexual features I like hair and jaw lines. Yay for me for being different. Haha. I get a gold star now.