Protagonist: Main character (s)
Deuteragonist: Secondary/Side Character s)
Tritagonist: Tertiary/Minor Character(s)
Antagonist: Typically a protagonist's foe (can be a duter-tri or even a protagonist)
Others: Authoritative Character, Parental Character, Villainous Character, Guidance Character, Foil Character
Use the D&D character creation template for traits, flaws, etc.