We, too, used "magic spray"...but what we did was buy an inexpensive mister. I added a little water and a drop of vanilla extract, then let my son spray all around the room to make sure it was "safe". Once he was done spraying, he put the bottle on the dresser next to his bed, just in case he needed it during the night.
Because it only had a small amount of water, I didn't have to worry about anything getting too wet, and the vanilla smell let him know it was working.
This was YEARS ago, but my now nearly grown son STILL talks about his 'monster spray' and we both laugh!