
We haven't seen much of the parents so far (a couple scenes, mostly dealing with SiWon in hospital and then the school one where Jiwook played the good brother.) So, judging the parents as shitty based on that is hardly comparable to the dark sides we 've seen of Jiwook. And again, I don't see abuse. Period.
Abuse is a strong word. I don't like it thrown around lightly.

maybe, but I doubt the way fox actand become like this [search punks] come from "no where", "with no reason" at all other then just himself. in the end of the day the parents and family have control on their children. even if you deny it, they still the one's that responsible on them!
in other words, I claim that he need a reason. other then you calling him a "devil" or just a "bad" guy. so yeas, it make sense the parents start all of it, even if they didn't notice.

Yes, the reason was resentment that he let become toxic because his brother was smarter than he was combined with the shock of realizing they were not One, not the same, that praise for one wasn't praise for the other, but separated.
And it does not make sense the parents started it, because why would they suddenly be doing something NOW, if not for 10 years previously? No, it was Jiwook whose shock at seeing himself as not One with SiWon, and realizing SiWon was appreciated more. That was the kicker, not the praise. Because trust me, the praise didn't just start that day and the parents didn't just suddenly change from one year or one week to the other. It's internal, mostly Jiwook's perception and choices, that was kicked off by realizing he was not the same as his twin.

I am sorry for your experience,but to say the parents is the ONLY one to blame is wrong. Yes they may be at fault,but only part of it. He has choices and he choose to be a jerk. I myself an Asian and i come from a low income family. I grew up with 1 brother and 2 sisters. My parents especially my dad really prefer my brother bc he is the only son. They dont say it directly,dont praise him more bc believe me ,majority of Asian family do not say things like i love you,we dont kiss between family member,its our culture. But it shows on how different they treat me and my brother. My dad almost never hv a proper conversation with me,he just works and works and ignore me. My mom is a selfish woman who never thought abt her children. My younger sister,who is 6 years younger than me is pretty and already has a husband while I never hv boyfriend yet. I often hear ppl talk how different my appearance than my sister is. She is pretty and has white skin and thin while i am fat and short and my skin is dark. Its bitter,and i often cry But I choose to focus on my study and now i hv been teaching math at school for 3 years. I dont hate my sisters and brother bc i know they r not at fault. I dont call them slut and I dont wish for them to die. So yes, Jiwook is at fault here.

first sorry to hear about your experience. that's why I said parents should not preffer/ praize one brother over the other. it's bad for them! and cause it does happen often. that's why we need to raise the awareness about this then deny it and blame only the brother.
in the end of the day the parents are the one that start everything, even if they didn't do it deliberately or wanted it to happen like this. I did say Fox have a mantel issues. I don't think you get what it's mean to have mantel issues, it's not like you choose to be born with mantel issues or choose to feel like everyone hate you. Especially at a terribly young age, that he didn't know how to handle those issues and it become worse. and the parents not only didn't bother about it [he run away from the party, that should have light a red light to them], I bet they didn't even try to look into it too much. I say it again, Fox does have some kind of mantel issues other then what he feel to his brother.
and they still preffer one child over the other. even if they didn't mean it to look that way, that how Fox felt for so many years! they should have talk to him about this and clarify that both of them are importent etc before it become worse like it already did... what I doubt they did. again, it is some kind of negligence, even if they didn't know Fox still their responsibility. and it's their responsibility to stop him from doing things like this, smoking and hung out with bad poeple. cause he need them the most!
and like I said, I didn't say he is an angel but he still suffer too! even if he hate and jealous to his brother. he acutally very interesting, in tearms of his psychology and in a way I think he do care for his brother. no matter how many times he scream he hate him and that he should die XDD but that just me. I like him cause he's not the strongest character ever, he do suffer even if people deny it and he is lost. even in the present time. but I hope Teamin will get him to stand up a little and stop talking to himself in the mirror XD
actually Teamin already doing a good job with him, telling him to find his own life and his own hobbies. I hope in the end, they be like brothers :D that would be so ironic and sad. but I"m too optimistic.
so many people [I seen in the comment saction] that still jodge and hate Jiwook/fox without even trying to get his side or knowing if it was even him that make his bro kill himself.
it kind of sad, to say the truth. cause it can happen to anyone, really. if they be in that kind of environment. environment that regularly compares him to his brother FROM A VERY YOUNG AGE!! not just his parents, not just his parents friends, it also his class mates! every day, all the time! HOW HORRIBLE IS THAT?!! this is also some kind of Bullying. not Physically, but mentally it still a horrible abuse!
now in the new ch, we see how much Fox/ Jiwook seek the most horrible punks to hung around with and to change himself to someone "bad" cause he hate himself enough to do that. how sad is that for a person to hate himself that much even if his brother love him the most!
to hurt his body with smoking and to be someone he's not. HE IS NOT A BAD GUY! he just weak and didn't know how to handle that abuse he got all his life.
maybe he started to think he "deserve" to be abuse cause he's a "bad" guy like they say.
I repet it has much has people need too! he just don't know how to deal with the Jealousy and horrible self esteem he got from his "great" parents and environment. and when he yalled at his brother, when he hurt his brother we see that part him thought he's happy to see him suffer has much has he is. but the other part, that he don't understand, that part was in pain to hurt his brother he love. and the more he hurt his brother, the more he hurt himself.
cause Fox hate himself enough, when it hurt him to see his brother suffer, he thought he "deserve" it. in a funny way, it just another way to hurt himself. cause he hate himself enough to want to do it.
so if I conclude it, Fox LOVE his brother the most!! he love him much more then anyone else and he fall apart all alone without anyone notice it! and now he will never get him back. it soo sad!! he's my new favorite character now! OMG (☆▽☆)