Used primarily by younger to middle-aged members of the South Asian Community, a Punju is an individual of Punjabi lineage, who is considered cheap. The derivation of the term comes from combining Punjabi with Guju—an alternative term for Gujurati, who are people from the northern Indian state of Gujurat. Gujuratis are best known for their frugal nature, hence the reason they are used to describe someone who is cheap.
Person 1: Hey man, doesn't Balvir owe you some money?
Person 2: Ya man.. but that dude is a Punju. He won't pay me.