Origin: random hyper-localised sayings, Rothwell, Leeds 1990s.
Person B: Ahh, no, because I have this COOPER MONEY!
I thought we'd run out of crisps, but I found all these cooper crisps in the other cupboard.
"man, whata cooper!"
"fo sho', hes a cooper"
"oh my gosh, jennny big was he???"
"he was COOPER big!!"
"holy cow so it was at least the size of your forearm???"
Originated as a parody of the extensiveness of the the popular Australian coopers beer range, in particular Coopers clear.
Often confused as a homage, or advertising for coopers. But reference was orginally intended as parody.
Luke: Coopers Tough Crowd
Julian: Do you want to go for a run?
Sam: Coopers exams
Luke: Coopers is that your real name?