The screams of children in the human world. Monsters university is a prequel to the animated film Monster Power Company 200 1. The story goes back to the college days of the main characters, Mao Guai and Dayan, and tells their adventures from bitter rivals to true friends. Monster Power Company is the largest power company in Monster World, which supplies the energy used by Monster World, referred to as "strange electricity". Their energy comes from the screams of children in the human world.