- Carol: The most impulsive and immature Thing represents Max at his core, being an optimistic yet troubled child with a temper.
- K.W. is his mother and sister rolled into one. Her loving compassion towards Max is his mother, and her loner attitude and not wanting to be around the other Things is his sister. She represents the older female presence, but through the differing approaches and may represent support in Max's life.
- Douglas: Douglas is Max's morality. Douglas is always there to calm Carol when he starts to act up, but it doesn't always succeed. A classic conflict between the id and the superego.
- Judith: Judith is the first half of Max's temper. She is the anger, passion, energy, and drive inside of Max. Though she can be aggressive and demanding, she is also fun loving and willing to do things.
- Ira: Ira is the Blue Oni to Judith's Red Oni. He is the second half of Max's temper. He is calm, passive, nonchalant, and indifferent. Though he is calm and collected, he's also a push over and very passive. He is the recessive half of Max's temper.
- Alexander: Alexander embodies Max's insecurity and feelings toward adults in general. Alex, like Max, is constantly being ignored, belittled, and looked over by the others.
- Alternately, Alexander could also further represent Max's feelings of being neglected and even apathy given the reaction to Carol harming Alexander, which could represent how Max is currently unaware or not understanding how his base desires cause him to get hurt.
- More inclined to think he represents the child's logic and reasoning. He acts immature sometimes because he's still developing, that's why he's the smallest monster, he can only grow if Max does as person. Even then he knew Max was never a king, just a regular human straightaway, but said nothing and keeps it a secret as it would only upset Carol.
- Bernard (the bull): Bernard is the suppressed sadness Max feels constantly. This is more than likely due to his father being no longer around, and his mother and sister being too busy for him anymore. Him not being involved yet always there represents Max not acknowledging his sadness.
While Max seems in a better headspace at the end, it often takes more than once to learn a lesson, leading to his mother taking him to a therapist and him getting diagnosed with conduct disorder.
Besides the uncanny physical resemblance, this also explains why John is so quick to accept that Crowley isn't human-he's seen fantastic Things before, so actual monsters aren't a stretch.
- Carol is the closest to Max in terms of personality, representing him as he is and Max nearly being eaten by Carol could represent how Max's selfishness is beginning to consume him, despite not wanting to hurt anyone. Max leaving is trying to come to terms to the fact to take other peoples' feelings.
- Which makes Carol's words on other kings being eaten allegorical. As in other children who have succumbed to their negative emotions and becoming adults who may not have been able to deal with the world properly.