I was just so shocked after I figured out that he loves her 0.0 At first I also thought that he really is her biological brother but then the reaction of Ri Jins mother revealed us that there is a story about the siblings and it obviosly has tot something with blood relation :) I quote the Ahjussi: "They don't look alike at all"

But not only his 'affection' for his sister gave me little creeps, also the fact that he behaves like a stalker towards Do Hyun...I mean this little fotobook of Do Hyuns live and his 'profile' board in his room...what the heel does he want from Do Hyun?! I can't say if he is stalking him in a bad or in a good way (with 'good' way I mean, like analysing his illnes and using it for his novells or smth. or even wanting to help him...)

So this drama just really got me hooked and I starve for more :D

What about you chingus?

HAHAHAHAAHAHAHAHA it seems u are the only one who saw this new section. AMEO 
Haha seems so, I've saw JI-Ns post few munits ago and immediatly thought of Kill Me Heal Me but I was expecting to already see some started discussions and participate in it but well... It's really new so I hope there will be ppl duscussing here in near future :D
it feels like oh ri on and oh ri jin might be connected to the tragedies that happened to cha do hyun in the past. I also think that oh ri on has some connection (might be blood related) to cha do hyun that is why he wants to find out more about cha do hyun's family background. 
I wonder if he is the missing child.  I don't know what he is up to with DH, but I don't think it is only book related.
I think that he's a child that dissapeared in that fire or something... since's Ri Jin said that he's afraid of it just like her. So, it must be something like that. Oh and I think that his feelings towards Ri Jin are not "brotherly" related, but something more. Since he's adopted, he knew it from the start and he could develop feelings for her. He was growing up liking her, but couldn't say anything, because he thought it would be wrong. Anyways, I'm so liking everything about this drama, a mystery in every character, mystery itself in a drama and a chemistry that is even better than everything :P
I think he's the missing child. What I really wanna know is the secret the chairwoman and DH's mom is keeping from him that could hurt him even more.... I'm so hooked! :D 
Even they're not biological, why can't they just be brother and sister? I like them more as brother and sister, but the patient in the hospital revealed it already (episode 4). Ok I thought Ri Jin is the adopted one, if it's Ri On then is he related to that family?
I hope despite his real feelings, there will not be too much about brother in love with his not sister. I like them as a family and story already is enough complicated to add such a thing.
Well, it's quite obvious to me after the 5th episode, that Ri-On is the missing child. The makers are not even trying to make it a mystery... as soon as somebody mentions "missing child" they cut to Ri-On pacing in his room... What IS a mystery to me is how much more messed up can that family get... lol... 
Also his feeling for Ri-Jin are clear... though I cannot know if he will act upon them... you can already see how cutely protective he is :D
Ri On must be the missing child and Ri Jin must have lived in that house or something as a child since she mentioned fire and basement.
I think that he loves her - duh - and I also think that this is a second (3rd) male lead that is finally fighting back !

But also I think it's a bit too much the push her around saying that you're protecting her. I don't know if it's jealousy or concern, but it looks like unbalanced relationship and lack of respect to me...