and when i saw minjae smile or moan while being thrusted in and ignoring the bullied kid so much stuff ugh
Yup. If he had set up someone who had actually hurt him instead of Eunsung or if Eunsung had hurt him but the Dad didn't realise that or if the kids had forced him to set up the man's son with no other way out I would have felt utterly sad for the kid he was and thought the Dad was a complete monster. As it is, I think the MC is a COMPLETE monster and the Dad is at most partially a monster, partially, because the dad is doing the same thing that you accused Mimjae of doing: not attacking the ones who were directly responsible for his son's death.
i remember when I first started reading this and I thought 'ooohhh sinful forbidden relationship and revenge when will the misunderstanding clear up abt the adopted son killing his son oooohh' BUT NO. THERE WASNO MISUNDERSTANDING. WHY DID HE SET THE IGNORANT KID THAT WAS NICE TO HIM AND SMELLED NICE AND NOT THE KIDS THAT CALLED HIM WEIRD OR THE ORPHANAGE LADY?! HE RLY ACTUALLYTHOUGHT HE COULD F*CK THE DAD OF THE KID HE MURDERED AND HAVE A HAPPY LIFE LIKE MINJAE HAVE U NO SHAME, DON'T YOU FEEL GUILT?!? AND THE POOR SPIKEY HEAD GUY FELL IN LOVE W AN IMPOSSIBLE GUY...!!! anyways i look foward to the author's next comic :3