Term for person in group who exemplifies untolerated behavior

Here are the eight roles tweens and teen boys play, according to Wiseman:

Mastermind - He is naturally good at figuring out people's weaknesses based on what would cause the maximum amount of public humiliation. He decides what is funny, stupid or cool.

Associate - This person is more talkative and more well-liked than the Mastermind. He's interested in everybody else's business and how the group can use information about people to their advantage.

Bouncer - Like a bouncer at a club, this kid is generally big and tall. He isn't good at verbally defending himself and he can't read other's motivations very well. He'll do what the Mastermind and Associate tell him to do, and that often gets him in trouble.

Entertainer - He's the boy who's the first to diffuse tension in a group by being willing to make fun of himself or making jokes. He has a hard time knowing when to stop joking around.

Conscience - Every group needs one. This is the kid who's worried about getting caught and thinks through the consequences of what the group wants to do. He's a rule follower.

Punching Bag - This boy is relentlessly ridiculed by other members of the friend group. He goes along with it because he doesn't like conflict and just wants people to get along.

Fly - This boy hovers outside of the group, or several groups. Guys can tolerate a Fly for a while, but they generally get frustrated with him because he isn't really a part of the group and they shoo him away.

Champion - He may be the only boy who doesn't conform to ‘Boy world' and is comfortable being himself. Most kids like and respect the Champion.