All that I can think of is this. If there is a genuine reason against the existence of this, and I'm sure there is, just saying "this isn't a thread for it" is ridiculous.

That said, I can't think of any NPCs that dual wield off the top of my head. Even NIN-type mobs only have one katana. My guess is that whatever they have set up that mobs don't have dual wield is what prevents Fellows from having it.