https://genius.com/Logic-nikki-lyrics
The idea of Nikki (nicotine) being a girl here really comes into effect. He feels like Nikki is an ex, and although he has other girls (drugs) at his disposal, they don’t give him the same feeling that Nikki does (nicotine addiction) and so he needs her back.
That means that all found names are not a person, but a product.
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