Magnate, in the sense of Morgan and
Vanderbilt, who are very well known for
controlling a vast majority of influence in their respective industries. Here, "chick magnate" refers to one man's near-domination of the female population in an average city-sized
geographical area.
Girl you're dating: "Hey, do
you know Riff Bankston?
You: "Oh,
that chick magnate? What about him?"
GYD: "I think we should have a
threesome with him."