中2008
Just Passing By for Soy Sauce
Just passing by, none of my business
Meaning
It claims indifference to public drama while watching as a passerby.
Origin
It came from a 2008 Guangzhou street interview about buying soy sauce.
How it's used
It is used to dodge comment or to describe a cameo role.
Example
I am just here buying soy sauce, so do not ask me.