|Real world information|
"Pinface's Dad" is an unseen character in the episode The Show that Dare Not Speak Its Name, in season 7. Pinface's father likely has the same bowling pins growing out of his skull that both his children do.
According to Grim, Pinface's family were originally from The Underworld, and Pinface's father and their family used to live across the street from a then-younger Grim and his family. When Pinface's Father got a new job, he had to relocate his family to The Netherworld.