I believe it was the little boy who is the star and protagonist of the movie, in a voiceover representing his older self reflecting back on events of his childhood.
Well, it's up to us to keep children from falling into the trap of this worldview.
There is a wider variety of social ties and interactions available for humans than just being a bully/victim (a "toadie" being a child who either dreams to become a bully or is afraid to become a victim). However, if a young human gets accustomed to the bully/victim behavioral pattern, there is a great chance that he/she will not learn other behavioral patterns at all. Why? Because the aggressor behavior provides that the behavioral pattern is forced on others. Accordingly, no new social skills can be learned. The victim pattern though, based on fear, provides that the victim sees everybody as a potential bully and is afraid to reach out and learn new social skills. Both patterns lead to problematic socialization, short-lived personal and social ties, anxiety, alcohol/drug problem etc. etc. Nobody wants it and nobody needs it.
So, no, there's no "fourth category - a bystander'. It's the "toadie". This is the essence of the psychologist's advice above: talk to the "toadies"! Tell them that other types of human interaction exist. Explain them that they are actually the bystanders whose role is crucial when it comes to the behavioral patterns around them. And
never use my wording when you do
It is anyway about practices and not words. Like, there are many ways how your toddler can play with the desired other child's toy without forcibly pulling it out of the other child's hands: you can trade, you can take turns, you can ask your parents to buy you the same toy. These ways may seem longer but they lead to keeping the toy for longer, too, instead of causing a scandal and losing both the toy and the playmate. The children can't know it though before they learn, so... It's up to the village. You did know the saying "it takes a village to raise a child", didn't you?
