Filtering what? Our poop?
The only filtering of our poop it does is getting it caught and then making you wipe 80 more times than you would normally have to
Let's get real for a second here. Outside of being annoying, looking and feeling weird, almost always catching shit in it and therefore making wiping a herculean task, being damn near impossible to shave, and just being kinda gross, what purpose does ass hair even serve?