• The term “闹双包” originated from the Chinese opera, The Case of the Double Justice Baos. In the story, on Justice Bao’s journey back to the capital after distributing food relief supplies, he meets a black rat spirit that transforms itself into Justice Bao’s form. This makes it impossible to distinguish between the actual and fake Justice Bao at the magistrate court later.
• The plot can be traced to Chapter Six, “The Lawsuit in the Dispute Over the Wife by the Real and the Fake Shi Jun”, of the classic book, The Cases of Justice Bao: Troublemaking by the Five Rats in Kaifeng. This is the story of the first rat among the five rat spirits, which transformed itself into Justice Bao and resulted in two Justice Baos who were indistinguishable.
• The term can also be written as “闹双胞”, which is associated with “双胞胎”, meaning “twins”.

A 27-year-old businesswoman claimed to have paid an advance rent of S$14,000 to the male agent but found that the house was double-rented. Although she had paid the money, she could not live in the house and the agent had also gone missing. (Lianhe Wanbao, 10/11/2008)