A Nice Cup Of Tea (HELP THREAD)

Use the cheese to get rid of the mouse just inside the mousehole

I appear to have run out things to interact with. I have made the tea and gotten ahold of the milk. As far as I can tell what I need to do is put the shelf up on the wall, then put the milk on it, so that the steam vapour defrosts the milk. However the shelf requires a screw, and there does not seem to be anything that I can unscrew anywhere. I can't unscrew the dresser or the dartboard and I can't put the milk in the sink and then pour the boiling water over it.

I have the following objects:

Spoon
Corkscrew
Screwdriver
Pot of hot tea
Kettle of boiling water (curently on the stove)
Sugar

There are no screws. You just need to be holding the screwdriver.