1: Means to tell someone to go away if they are enoying you.
2: When you want a wench to clean out your corn hole
1: Bob: Hey Joe can I borrow your car for the weekend? I wont crash it like the three other times.
Joe: You know what? how about you go eat some ass.
2: Man I took a huge shit the other day and didnt wipe. Im going to make my girlfriend eat some ass.