The "Antagonists" category covers characters who actively try to impede the progress of the protagonists/pov characters either once or for multiple instances.

Note that an antagonist is not necessarily always evil, but can merely have opposing actions, thoughts, motives, etc. to (in a story) the protagonist(s) (for example: Dr. Scratchansniff working with Ralph and Hello Nurse to capture the Warners in "Piano Rag"). The term does not say anything at all about the actual personality of the characters. It is simply a plot role.