I'm living where the nights is jet-black
The fiends fight to get crack
The streets are dark in two senses: poor neighborhoods in New York City tend to have poor infrastructure, and thus streetlights can be unreliable. But it’s also just a dark world: drug addicts fight each other over drugs at night time
“Jet black” is a reference to black culture, since the magazine Jet covers the African-American community in detail.
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