Coke ass
When your up all night doing cocaine and then the next morning you have to fart and shit constantly letting out all the Coke from the night before.
Chris: man I've been farting and shitting my ass out all day today I can't take it anymore!! Matt: what did you do last night that your like this? Chris: I went to the comfort zone and did a bunch of Coke with some hookers I met! Matt: well bud it sounds to me like you got yourself a good ol case of "Coke ass" Chris: goddamit I was afraid you'd say that!