The Cosmic Owl's design is based on the lighting above a urinal at Cartoon Network Studios
His voice resembles the voice of Dr. Phil McGraw.
There was a graven image of an owl with purple gem eyes on the top rail of the library chair in the episode "The Real You," which may be the Cosmic Owl. This may suggest that the Cosmic Owl is a god of knowledge because the symbol of Athena, the Greek goddess of wisdom, is an owl.
The Cosmic Owl may also be a psychopomp who guides souls to the Land of the Dead, since he is so important in croak dreams.