In this world, there are those who have never played games according to the rules.
Eren Morton was also such a person.
Considering what some of the certain 'nobles' were doing, and [Sharpened] club also belonged to that group, the fact that Eren's bracelet was tempered didn't surprise me.
This is how the games, books, shows, or comics work.
If the person that is committing the evil acts are person belonging to the main cast, be it the main character or secondary leads, in the end audience will approve of that act.
It is very easy to distort the perspective of humans.
This was exactly the case in the game.
Eren Morton was a bastard who never played fair, but even then he was a liked character, both fairly because he was a wingman for Arthur and his actions showed on the screen lightly.
However, if you look at all those scenes as a human, the things Eren did were nothing but dishonorable.