A relatively new interrogative phrase, independent of the preceding verb tenses, used to emphasize the extreme nature of the preceding clause.
The phrase has its origins in the Atlanta Public School System. In its most common incarnation, it's said with a humorous, yet sassy look over one's glasses, or general "girlfrand!" attitude.
A phrase said, usually while gaming, but can be applied at any point in life, when one feels unstoppable or after achieving a difficult task.
Synonyms: Winning
In CS:GO, friends are playing. It gets down to 5 vs 1. The 1 makes an ace by killing all 5 opposing players. He shouts over the mic, "Ain't No Brakes on the Rape Train!!!"
An Aint shit ass nigga is a dude who will never amount to shit. He will never want to amount to shit, never will accidently amount to shit, and is never going to aspire to amount to shit.
Man that dude Chris Hendrix is an ain't shit ass nigga, he ain't got a job or a hustle and his dick is so small it looks like a pussy.
No problem. Don't worry. I/we've got this. I/we can handle this situation. This is not a major concern. This is easy. This an easier task than it appears to be. I/we know what we are doing in this situation. "This is as easy as American Pie."
{{IMPORTANT NOTE: It should be noted that this is whimsical and ironic sarcasm. The person saying this is only ironicallypretending to be polite. It truly means "Get off my stinking back! You should know by now that I already know how to do this."}}
A new manager at a restaurant (to an employee at a Pizza place who has worked there for ten years): Can you make this guy's special order? It's a really strange request.