Ketchup Keeper

I was having an issue at work where my Heinz Ketchup was disappearing at an alarming rate. A note on the bottle didn't work, so I searched google for bottle locks, and found this great creation:
https://www.instructables.com/id/Beer-Bottle-Lock/
I was inspired to make one for my precious Ketchup bottle to thwart the Ketchup thieves.