booby trap bate
Masturbating in a room (most commonly the bathroom) with the door left unlocked in the hopes that someone will walk in on you and catch you jerking off. Similar to but not to be confused with maid bating.
When my mother-in-law is visiting, I like to have a booby trap bate in the guest bathroom. I would love to see the look on her face when she see's my throbbing hard-on!