I dont understand why yall are hating and disappointed at gyeonyob like yes hes bad but wa...

I dont understand why yall are hating and disappointed at gyeonyob like yes hes bad but wasnt he already like that from the start??? its so unexpected to kill his friend but it was not that surprising its realistic for him to go through such measures when he already planned to kill that guy for revenge this isnt some dattebayo shit where the mc preaches about the power of friendship yall its not always going to be that way