A person who goes into the bathroom, and tries to open your stall door over and over, even though it is obvious that someone is in there; causing you to tense up and cut off any turds in progress.
In the 16th through the 18th century there was a great deal of unsactioned raiding and pirating going on in the seas of the newly discovered Americas, the perpetrators of these acts were called Privateers.
Here in the 20th and 21st century there has been a large increase in the amount of homo-eroticism in the world at large, leading to many new slang terms for the anus which is commonly associated with homosexual sex. One such term is Bung.
So logically a Bungaleer is one who engages in privateering of the anus.. or more commonly Ass Piracy