I don’t much like Amon or Echo, but I do appreciate how they were written. They were written so you would not like them, but at the same time you can’t help but feel sorry for both of them.
Amon had these feelings of jealousy and hatred for his little brother Sid, who gained favor with their parents because he was their blood son while Amon was adopted. If Sid did not exist, Amon would inherit everything, the company, wealth, and power. Amon chose not to kill his little brother because Echo told him he was not worthless when he felt like he was. Since then, he chose to bury that hatred and jealousy so that he would live for Sid, but these feelings and desire for power transferred to Echo, and she now carries these feelings that Amon threw away. She’s like the embodiment of Amon’s inner darkness. And the path they they are now on will lead them both to their downfall.