What is Scrub The Pig?
To 'scrub the pig' is to have a wash/bath/shower.
e.g.
I can't come out just yet, I've got to scrub the pig first.
OR
Gees that guy smells like he's got a dead rat up his arse. He can't have scrubbed the pig in a week.
See wash, shower, bath, spruce up, etc