A twat-tac is a non existent vaginal oder remover. Sometimes it is used to refer to Vagisil Rephresh, and other vaginal oder medications.
I was about to go down on this hot chick that I brought home from the bar but when I removed her panties I realized that she really really needed a twat-tac. The smell was unbearable.
sloth-panties is a slang term for dirty womens underwear. The dirty underwear is usually worn around the house at night, to sleep in, and will always have stains and dry vagina leakage stuck to them.
I was really grossed out when my new girlfriend came into the bedroom and got undressed and proceeded to put on a pair of sloth-panties.