It's from this stupid YouTube chain letter: "PLEASE I BEG U DONT READ!! I REALLY HAVE TO THIS.
in 1985 a girl named jenny was walking by a nearby river.a mesterious stranger killed her by stabbing her in the heart and hanging her in his/her closet. before killing her she/he said "hanghangeara". now that u have read this, she will appear in ur closet hanging there with her glowing red eyes. to be safed repost this to 3 other videos" That is how it appears.
The word bangarang is actually Jamaican slang and is defined as a hubbub, uproar, disorder, or disturbance. Used often in the movie "Hook" by the lost boys
"Yo, that meal was bangerang!"
"BANGERANG PETER!"
"Oh word, that chick looks bangerang tonight"
"We're gonna make a bangerang of a party up in here"