In Pixar’s Monsters, Inc., the blue monster ranked as the company’s top scarer is Sulley. James P. Sullivan, commonly called Sulley, is a large blue monster covered in purple spots and the film’s principal protagonist.
Sulley is an exceptionally successful scarer at Monsters, Incorporated. He works closely with Mike Wazowski, his best friend and assistant. His position changes after Boo enters Monstropolis, forcing him to question the company’s assumptions about human children and the meaning of fear.
Sulley should not be confused with Randall Boggs, who competes with him for the top scarer position. Mike is Sulley’s one-eyed assistant, not the leading scarer. Sulley’s full first name is James, but the film consistently uses his nickname, which is the short canonical answer here.