Word for a "urban parasite"

can you please define a word for a someone who comes from the small city to the big one just to make own life better? This person must be local citizen, but it keeps rude thinking, does not want to get a normal job and looking for an alternate ways to move on, like a marriage or little criminal actions, but with no violence.
Russians call it "Limiter". How Americans do? Can’t find out that.