you must have a hairy ass for this to work. its when you take a huge extremely wet shit and you wipe your ass and shit gets stuck in your ass hair without you knowing and becomes crusty.
Asscresting is a facet of foreplay that involves snuggily placing the erect penis in the middle of the girls(or guys, asscresting is applicable to sexual orientations of all kinds) asscheeks and sliding or rotating in any desired direction. It is essentially grinding without pants on. Highly convenient and surprisingly pleasurable, asscresting is on the rise as an act of foreplay and i encourage anyone interested to experiment. Don't knock it till you try it. dicks.
"Yea she wasn't ready for sex so we just asscrested, it was chill."
"Dis bitch wuz on her purriod so ya boy was asscresting dem cheeks all night."
Student A: What'd you get on the science test?
Student B: 64. Mr. Bober's a dick.
Student A: Really? I thought it was easy; I got a 110!
Student B: *glares* You cocky ass crust. Piss off.