This sentence is an idiomatic expression referring to someone who is expressing an extreme need for
money as soon as possible as if their rent was due, this can materialize in working extra hard for your
money and or doing extreme begging.
This sentence can also be used as a question, "Is your rent due?" meaning "Do you need
money?",
as a statement, "Bro's rent is due" or "Rent was/is due" meaning "That man really needs
money" or "I really need money"
and as a adverb, "Bro is acting like his rent is due" meaning "He's working very hard to earn that money, almost like his rent is due."
Guy 1: *Doing extreme stunts while panhandling"
Guy 2 (roommate): "What the
hell is this
guy doing? I don’t remember our rent being due."
Guy 1: "PLEASE GIVE ME
MONEY"
Guy 2: "Is your rent due?"
Guy 1: "I'll do anything for 10 dollars!"
Guy 2: "Bro's rent is due"
Guy 1: *Starts breakdancing widely on cardboard behind a tip jar*
Guy 2 "Bro is acting like his rent is due"