He is a customer of Ink Inc. and in the official game website, it is revealed he only goes to Ink Inc. shops to get tattoos at a cheap price.
That pedestrian can be rarely found outside the Gas Station on Grove Street in the early stages of the game. He may talk with Franklin and Lamar when they are together. He is heard saying, "Yo, what's up Lamar?" and "How's it going, Franklin?". Franklin cannot talk to him further however.