>>214343539
Exactly. It's the fact that he's just added pressure that makes him interesting as a character. He's just following the rules and representing a countdown that the protag has to meet the conditions of their agreement or to outwit him.

In one of the behind-the-scenes special features, Doug Bradley said that Clive offered him one of two roles in the film: either The Hell Priest, or one of the guys moving the mattress into the Cotton home at the beginning. He said that he picked the first one because it had more screen time, but he was worried that the make-up would obscure his face too much and hurt his credit as an actor.
I think it's this really understated approach that made the character such a hit. They didn't rely so much on it, and it just happened to be awesome and develop a fanbase naturally.