The phenomenon in which the threads or material of your undergarments become intertwined within your hair of your ass crack, creating small, dense balls of fuzz. These then fall off when bathing or cleaning the anus, spreading themselves easily around the shower or bathtub. They can also be encountered within unfortunate instances of oral sex.
What the fuck, our shower is so fucking gross, I wish Alex did not have such bad anus fuzz.
Oh man, I gotta get outta these pants, I have major anus fuzz.
Dude, he went down on her, but she had a fuckload of anus fuzz, so he just bounced.