Virtually nothing is known about him. He is reported to be even keel, calculating, and unempathic.
He is said to have limited mind control. It can't penetrate ABW Filters, but the effect is powerful and can exist independent of his presence. Meaning he can control almost anyone, even at great distances.
Through the things he has on his patrons, Bal is virtually untouchable.
His club is incredibly hard to get a membership to, but it is said to be very worth it. Each member carries a card, is catered to on hand and foot inside the club, and pays steep dues.
According to urban legend, for the pricey membership dues, any perversion or dark fantasy is made reality. Anything you want, no matter how illegal or twisted, Nightingale's capable staff will work to accomodate it. It has been suspected that it's an illusion of Bal's mind control, but evidence points to that not being the case.
Judges, Lawyers, cops, and nearly anyone else in power is a card-carrying member of Nightengale's, although they'd rather die than admit it. Through this power network, Bal has centered in a neutral area where no one dares mess with him.