Walk the Shih Tzu dog 

To walk the Shih Tzu (commonly pronounced Shit Zu) is a slang term, used to denote the act of human defecation. Shih Zu being a breed of dog, originating in Asia, having to walk the shit zu does not refer, in this context, to providing one's pet dog with exercise, but in fact the impending urge of a human to defecate.

'Hey Joe, wanna go to the bar for a few beers?'
'Maybe later Ray, I gotta go walk the shih tzu dog'.

'I had a bad takeaway curry on Saturday and I spent the whole night walking the shih Tzu.

Walk the Shih Tzu dog by Jotinmick June 13, 2017