At the beginning of LotBS I dismissed Chi Hyun as a rather boring and unimportant character, but as the story grew more intricate he gradually became this complex and truly interesting character. He’s neither villain, nor the stereotypical second male lead. Born to a pair of truly deplorable parents - both psychopaths and murderers - he has somehow managed to grown up into a genuinely good and decent person, sensitive and caring, who loves his mother and stepfather. Yet for some reasons, he doesn’t inspire in other people such fierce love, loyalty and admiration the way Joon Jae does who commits actual frauds and keeps almost everyone at arm’s length. Since the very beginning, he’s been such a deeply misunderstood character both by most viewers and Joon Jae, who blames him for his misery the same way he blames his mother. And just like Joon Jae remembers about CH only the bad memories - particularly the photo incident which was simply a mere case of a boy’s teenage jealousy - HE COMPLETELY FORGETS ALL THE TIMES HIS STEPBROTHER HELPED HIM; when he literally saved his life by damaging his mother’s phone, when he hid the pills, when he told him about Ahjusshi’s accident and his father’s declining health and told him to protect him, but Joon Jae has never truly listened to his warning.
CH’s has always been torn between his love for his mother and his stepfather. And now he is choosing his mother because he finally understood that his stepfather will never love him the way he wants. Probably the most heartwrenching and revealing moment in that regard was when he listened to Chairman Heo bequething all his possessions and property to Joon Jae. It’s not because CH would crave the money, but because of what it represents - in that moment his stepfather completely disregarded him and their time together, only thinking about Joon Jae. Even a small thing, a book, would be enough to CH because it would show to him that he is loved by him. It has always been clear that CH has accepted the fact that his stepfather would never love him the way he loves Joon Jae, but he always hoped at least for some semblance of love, but seeing that his stepfather has never truly loved him breaks him. SO it’s natural he chooses the one parent who always loved him. What is truly interesting that both his mother and MDY, his biological father, try to protect CH from their terrible past and action - maybe there is hope after all for them, a proof that even evil can love.
It’s a mystery what CH will do now - one thing is whether he simply stops protecting Chairman Heo and remain silent about his mother’s actions (the truth is he is almost completely unaware of the full extent of her criminal activities) or whether he will become an active participant.