Why did they kill this person?

TheBoy627
There was an event where an entire highschool class went to jail because that whole class participated in the brutal murder of a brave weird introvert boy who often beat and humiliated his bully. This event didn't happen in the USA. This event didn't happen in North America, Central America, South America, or the Caribbean.

The highschool whole class murdered the weird introvert boy because he often beat up and he often humiliated his bully physically and verbally.

The bully was a classmate of the weird introvert boy. The bully was an ordinary kid meaning he was not a popular "cool" kid but he was also not an outcast. The bully has a healthy social life. The weird introverted boy is quiet and has no friends. He preferred to have no friends.

The whole class only bully the weird introvert boy verbally and socially by making fun of him, using insults against him, spreading nasty rumors about him, and ostracizing him but the weird introvert boy doesn't seem to care and also prefers to have no friends.

The entire class bullies the weird introvert boy because they hate him. They were also extremely angry towards him because he often humiliates his bully.

Why did the entire class murdered the weird introvert boy? Why did they go that far?

Why did all of these happen?
Updates
10 mo
The bully is not friends with most of the whole highschool class but all of them do not hate him. All of them respect him and are just neutral to him. The bully only has 4 friends within the whole highschool class.
Why did they kill this person?
7 Opinion