Ian is a character who appears in the data files, but not the actual game. He can be added to free-roam through hex editing, and he will appear in the New Coventry area.
He is white, with facial stubble, a plaid shirt, and a blue headband. Nearly all of his dialogue includes the words "yo" and "gangsta." He also refers to fireworks, particularly when saying goodbye to Jimmy, and it is speculated that he was somehow associated with a fireworks shop that was cut at some point in development.
His voice files contain the same set of dialogue that would be used for a standard townsperson. It is possible that he was supposed to appear among the New Coventry townspeople, and that his removal is why Denny was changed from a shopkeeper to a townsfolk. The data files list his position as "Associate," and give his name as Ian.