Having to urinate very badly or urgently.
"I have to take a living piss!"
"He drank so much at the party that after he took a living piss!"
The very CORE of someone's being; Absolutely EVERYTHING they have: physically, mentally & spiritually.
"Frank beat the LIVING PISS out of Dave the other day. It was hard to watch."
"Dude, that movie scared the LIVING PISS out of me! I've never been so frightened in my life!"
When a dishevelled ginger man enters the living room of a house and doesn't leave until he is 100% out of his mind from drinking tinny's all day or consequently blacks out.
Guy 1: Ay' up where's Doug?
Guy 2: Did he not turn up for work today?
Guy 1: No.
Guy 2: My guess is it being a Monday he's most probably still living room pissed.