My nipples? I love to have them sucked. Nibbling on them is very nice too, not to mention being pinched a bit. I'm not into the aggressive biting and such though.

Bellybutton?? you mean to tell me that that's supposed to be some sort of erotic zone?
Seriously, when it has been touched it generally tickles, probably though its because no-one has paid much, if any, attention to that area on my body.

Same goes for the area just above my package.