it's feeling like complete shit. quite literally, you don't just have one asshole producing shit, but a whole sack of them.
or
someone who looks disgustingly beat or ugly.
Damn, I got so wasted last night i feel like a whole sack of assholes.
or
Shit, Carly is one ugly sack of assholes.
The ultimate slogan to be used when a female is absolutely positively ugly and there is only one way to describe her ugliness. This may be confused with fugly, however this reference trumps the fugly category.