As a derivation of Jobbie (a Scottish colloquialism for excrement) a "Jobbie Weeker" is a poo of considerable satisfaction. For example, a ghost poo might be considered a "Jobbie Weeker".
The turd which is produced after living on crisps, coke and chocolate bars for several days. Its a hideous, grey and sometimes hairy turd which smells so bad it can cause buildings to be evacuated for months.
I've been living off the vending machine at work for a week. I think I'll soon be dropping a Briggsy jobbie.