This phrase is an odd variation from the regularly used phrase "that sucks". There are two main definitions of this:
1) in literal terms, putting your mouth to an anus and quickly inhaling, causing a stream of air to be pulled into your mouth from the anus.
2) in slang terms, to be bad. This is how the phrase is most commonly used, and tends to be more intense than the usual "that sucks." "That sucks ass" is like adding a "really" to it.
"She sucks ass!"
"Not like that, man"
There are threes types of pocket foxes:
1) the fox that only lived for 15 minutes in the 16th century, the insides of it's pockets are the strongest aphrodisiac on earth.
2) the one currently living is small, white, and has glowing blue eyes. It has pockets on it's sides. They have tons of fleas, but you will usually not notice because of the third type of pocket fox.
3) the hampster-shaped creatures that live inside of the second type of pocket foxes pockets. They are also called pocket foxes because people used to think that they were the offspring of the second type of pocket fox. In exchange for getting to live inside of the pocket fox's pockets it eats it's fleas, which also gets it an easy meal.
1) Mr. Burns was able to have sex after taking the pocket fox's aphrodisiac
2) The pocket fox is the coolest animal ever!
3) This pocket fox lives in the other pockets fox's pockets!