He has no respect for privacy, and is not above blackmailing others. He does have a tendancy to spoil his son and nephews, however.
He is the only member of Slender Man's family known to have hair. He also smokes, and speaks in an exagerated New York accent. He is often seen wearing a fedora, white shirt and tie, and black pants. He also has a taste for leather wrist watches, and has a collection that he keeps He also wears a pencil behind his...actually, he doesn't have ears, so how the pencil stays in place is a mystery. Then again, he and the other members of his family can see and hear without eyes or ears so that's not very remarkable.
He used to work for a gossip magazine, until he wrote a scandalous article about his boss, who then blackmailed him after discovering Slander Man does not actually have a face and blackmailed him to get him to reveal his article to be a hoax, and Slander Man has been trying to get revenge ever since, and has started his own gossip magazine.
Because of his gossip magazine, he is very wealthy, which is why his son Trender Man can always afford the best clothes.