Does he leave it there overnight? Take it one night and have it chromed or bronzed.
You could use a knife and slice it a few inches from the tip, but don't slice all the way through it. That way, after a couple snaps the tip will the snap right off.
Bring a air horn to work and blow it every time he cracks the whip. Better yet, have everyone bring in an air horn.
Get some fake blood and when he cracks it say, "Please for the love of God. Stop it. My ears can't take it". And if he's an ass (which is sounds like he is) then he'll crack it again. That's when you put your hands to your ears as if you're in pain and then with the fake blood make believe your ears are bleeding.
hmmmmm, what else...
One of you employees write up a phony magizine article that looks like it came from Playboy or something like that. And have the article go into detail about how men who use, handle, display, and play with leather whips are just trying to compensate for their extremely small *****es.
mmmk, there's a few ideas. If I think of any more I'll come back.

uT