What is Bag Of Shit?
1.
1. noun: A bag full of faecal matter, otherwise referred to as "shit"
2. adjective: Used to describe something so bad that the adjectives 
3. Adverb
Sometimes hyphenated, said as one word.
"Avril Lavigne is a bag of shit."
"They performed bag of shittily.
See 
Random Words:
1. 
slang term for 'really?', 'for real?' or 'seriously?'
But can have a wider use colloquially as a one word.. 
1. 
Another word for a Faggot or a Dooshbag, who is in love with a woman who has no tits with ugly face.
Bob: Jason is such a Hollenbach-La..