What is signified by the envelope left to Balram by Pinky Madam?

The envelope that Pinky Madam leaves with Balram at her departure – or, more accurately, the money it contains – plays a key role in a later circumstance in the narrative that propels Balram even more strongly towards his determination to live the life of an independent, wealthy, successful man. He later uses this money to pay for the services of a blonde prostitute.