She's at a stove
Can't believe I got her out here cooking dope
The protagonist has corrupted this girl, and turned her towards a life of crime and drugs. Here he expressed his regret at having got her caught up in this seedy underworld.
However, Frank himself, did not necessarily corrupt the girl, as she’s lost so she’s deluded and thinks this is the life.
The girl is so caught up in the fast lane and presumably the money and false sense of excitement and love she receives from Frankie, when in turn she is just a source of drug trafficking for him.
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