You call someone an "Ass Cheese" when they do something really dumb that pisses off everyone. This word was invented during Lunch recess at Zion Heights Middle School when SOMEONE kicked the class 8-1's only volleyball over a fence.
George(fake name) : *Kicks volleyball over the fence during lunch recess*
John(fake name): Great Job you !@#%ing ASS CHEESE!!!!
George: Duuuuuuuh
John: *beats up George*
when it's 100 degrees out and you weigh 230 pounds and you go to the 7/11 to buy an extra-large fountain soda and by the time you get home there's an ocean of sweat between your ass cheeks going all up into no-man's land and you try to wipe it off with your shirt but realize it's too much so you grab some paper towels and wipe it away. then you smell the paper towels because for some strange reason you like the smell of your own ass.
Those pheromones you think you're attracted to are probably summerass cheese.
When you shart in your pants and your in such a situation that you can't immedietly get somewhere to change your underwear or you don't realize there is actual poop fermenting inside your pants so you don't think to change your undergarments or you don't care enough to change your underwear. The stinky fart solution saturates your underwear and begins the aging process much like aged cheese.
"I went on a camping trip and accidently sharted. I didn't have an extra change of clothes so I had Ass Cheese growing in my shorts."
the hot musky sweaty and maybe a little shitty residue left on the asshole after going toilet and not wiping very well which gives off a strong smell and can be very tasty
i spread her ass cheeks apart and rubbed her asshole and could smell her sweaty musky shitty ass cheese on her asshole that wasn't very clean and i licked it