It depends on what you're doing with the biography. Do you want feedback on your character, or do you just want a place to list off your OCs?
By the sounds of it, you just want a place to discuss about various OCs people have come up with. If you're looking to develop your character more, the
Plot Bunny Thread might be what you're looking for. If it's just a discussion, then you can create a thread in the
Writer's Lounge to hold a discussion with your fellow writers.