The Ring Leader is the person that leads on the bullying but doesn't always start the bullying
The person who is being bullied
Actively involved in 'doing' the bullying
Supports the bullying that's currently going on
Stands up for the (target) person that is being bullied as they know how wrong bullying is and are quite confident to stand up to a person that is doing wrong. This could also involve talking to a responsible adult who has the power to actually do something about it
Ignores any bullying and does not want to be involved in the situation