it is your breasts because when you pull them out and let them go, they go NUNGA NUNGA.
made up by a gross older brother in Confessions of Georgia Nicolson, me and my friends now use it frequently
"in gym class her nunga nungas were bouncing all over the place."
can also be used like: "this shirt makes her nungas stick out", and "he put his hand on my nunga."
Quite literally nude-colored pants, and you know what nide-colored pants are? They are no pants. So if you are in your nuddy-pants you are in your no paints, i.e., you are naked.
Dancing in my nuddy-pants means dancing naked.