In this game he doesn't appear to have much of a central role at all. In fact you just happen across him at one part of the story, then he shows up later on driving a mini-van of sorts, selling random crap. I've seen 3 inventory possibilities. The plugin chip stuff may be good for a quick fix for something, but the slot points they use are extremely high. Probably even the maximum possible.

After that he's apparently got a sidequest or two, then you can fight him as an optional secret boss - although apparently it's recommended you be level 99 when you do.