Cleo De Nile is 5,842 years old and is the daughter of the mummy. She has the haughty attitude of an Egyptian princess, plus the looks.
Cleo has a very bossy attitude and hates it when someone disobeys her orders. She usually gets along with everyone, but she has a tendency to say things before thinking them, which makes people go against her. Her actions go the same way.
Like all the characters, Cleo is introduced in the episode "New Ghoul @ School" which shows off her bossy and arrogant attitude when she bosses Ghoulia Yelps around and makes fun of Frankie Stein.