The Boo Theory. Boo is a central character in Monsters…, by RyTheories, Applaudience

In Monsters Inc, a prominent character is Boo. Obviously. However is Boo a main character in Monsters Inc or is Boo the central character in many Pixar and Disney films. There is a theory that Boo…

Was Boo From 'Monsters, Inc.' In 'Brave' This WHOLE Time? - Inside

This grand unified theory explains how Monsters Inc.'s Boo grows

The freaky Pixar theory that could blow your mind - CNET

Everything We Know About Boo

Was Boo From 'Monsters, Inc.' In 'Brave' This WHOLE Time? - Inside

Was Boo From 'Monsters, Inc.' In 'Brave' This WHOLE Time? - Inside

Why That 'Toy Story' Theory for 'Monsters Inc.' Just Isn't True

The Boo Theory. Boo is a central character in Monsters…, monsters

Was Boo From 'Monsters, Inc.' In 'Brave' This WHOLE Time? - Inside

Bring an Obscure Relative to Work Day, Pixar Wiki