
Mike and Sulley begin to build a friendship as they compete together. Mike and Sulley join the Oozma Kappa fraternity to qualify for the Games. Sulley joins Mike, despite Mike's protestations. After failing the class, Mike works out a deal with the school's dean to re-enroll in the program on the stipulation that he wins the Scare Games. This dislike escalates into a major disruption made in class. Mike initially dislikes Sulley for his arrogance and bad work ethic. Mike gets accepted into Monsters University's scare program where he is introduced to James P. On a class field trip to Monsters, Inc., Mike is inspired to become a scarer professionally after he followed a scarer onto the scare floor. Mike had a lonesome childhood and struggled to make friends. and Monsters University, Mike is depicted as a proud monster. Mike Wazowski is a green cyclops-like monster with a round body, two small horns, thin arms, as well as four fingers and three toes.

Sulley and Mike start as arch-rivals in their introductory scaring class but eventually become friends during their teamwork in the scare games and lab incident, with the relationship persisting even after their expulsion. Monsters University depicts a younger Sulley as a talented but lazy student whose father Bill had made a name for himself as a proficient scarer, believing that he can rely on merely his attributes to excel in class. In the first film, he is "The Best Scarer" for several months running at the start of the film.

He excels at scaring children, but is kindhearted, thoughtful and has a relaxed, amiable personality otherwise. He has muscular limbs, a reptilian-like tail, dorsal spikes running down his neck, back, and tail, and feline-like fangs. "Sulley" Sullivan is a 7 foot 8 inch (234cm), furry light blue and purple spotted monster, with a humanoid bear face, devilish horns, dark blue eyebrows, and a visible nose of that of a big cat.

