A fork of Rural Dictionary
The shoulder demon is the foil to the shoulder Angel and the term is used to make more sense when talking about the two because there can be multiple angels and it makes sense for everyone to have one but, there is only one devil so it makes more sense for everyone to have a lower rank demon to act as a more appropriate being that works in opposition to the shoulder Angel. Ex: Crowley is a demon in Good Omens and works for satan/the devil. (Extend your disbelief because Crowley isn’t actually a shoulder demon but the concept is still there when it comes to hells hierarchy)
His shoulder demon was telling him to steal the cat.