"You humans are the lowest forms of filth on this planet. No wonder the flies are attracted to you constantly. You reek of sin and malevolence. You are not even considered humans...but asses."
Beelzebub is a high-ranking demon, and was originally a Philistine deity named Baal Zebub, who is considered one of the seven princes of Hell, he is famous for being the "Lord of the Flies" and is arguably one of the unseen antagonists in the book of the same name (however this is debatable as the book focuses more on human depravity than the supernatural).
Beelzebub is also often confused with Satan and the two names can be interchanged, however, strictly speaking they are two separate entities and in some tales Beelzebub led a revolt against Satan to become the lieutenant of the Order of the Fly and gain great power from Lucifer, the Emperor of Hell himself.
Beelzebub is seen as being associated with Pride or Gluttony depending on the scholar and is also the prince of false gods; flies play a large focus in imagery detailing him and the malignant spirit can even take the form of flies according to some.