Taekung is guilty for not going at Heejae face-to-face to resolve this thing.. but the accident was more of heejae n the secy's fault.. majorly the secy, for letting heejae borrow his bike and ride it all alone when he knew heejae can't really ride it well, just bc he wanted to be friends with heejae.. although he didn't know it would snow, but he had enough experience with biking to know how dangerous it could be to ride a bike all alone at night when you aren't used to it..
You are right that Heejae and secretary are at fault for the accident. Heejae was not mentally ok but he still rode the bike to meet up with Taekyung. Someone mentioned that after being pushed by his brother, his brain already suffered trauma. and the incident just hit the nail in the coffin.
Now, he really regrets what happened even though he doesn't understand why he rode it. It's kinda ironic how he wished he is not smart because his brother felt threatened but now that he is like that, he regrets and hates his past self.
I think, if the brother didn't hide the fact that heejae got into an accident. Then, there will be no misunderstanding.
That brother is a real a-hole.. first he hated heejae bc he was too smart and now bc he isn't anymore.. I think he hid the fact that heejae got into an accident bc the business partners and other people will blame him for not taking care of the future heir..
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Ahhhh i already firgure it out when Taekung mention the sea on a snowy day and the accident!!! GAHHH I hope Taekung feel extremely guilty like I hope the actor guy know about the reason why heejae never showed up so he can mention it to Taekung n rub it in his face of how Taekung is being so petty. Like i think he got the best personality to make Taekung to feel guilty