Mulctuary Money Management
Arthur Poe was the financial banker in charge of the Baudelaire estate. He was in charge of protecting the Baudelaire fortune for the three siblings and finding them a legal gaurdian. He worked at Mulctuary Money Management bank in the position of Vice President in Charge of Orphan Affairs.
He is usually blatantly ignorant of Count Olaf's disguises, and he has never listened to the Baudelaire orphans nor believed them when they were allowed to speak their minds. It is also revealed by Count Olaf that Mr. Poe had a stage name, although is it not revealed what the name was.
Arthur Poe has two children: Edgar and Albert, and a wife, Polly. His sister, Eleanora Poe, is believed to be a V.F.D. member as well as the Editor-in-Chief for the The Daily Punctilio; she assigned Lemony Snicket to be the dramatic critic for the very same newspaper.
Lemony Snicket hints in book 12 that Arthur Poe eventually dies from a harpoon incident. He also, supposedly, hid secret documents in his hat at some point.