most likely a large female raggie walking down the sidewalk and you notice that their tits are so big they hang below the belly button. And the first word that comes into your mind is wallowing whoopies. Because it is so disgusting and that's the sound you'll be making when your pulled over in your car vommiting on the side of your road.
"look at that chicks wallowing whoopies"
"I think I'm gonna be sick (waaaaaalllloooowwwing. Whoooooooooopiessss)"