No, it was always him, his mother and his sick brother, his father is out of the picture. In the ch 0 and 1, I'm assuming that maybe his dad is the bad guy, that with the deaths of mother and sick brother, and teach trying to protect their last memory, finally the dad got tired and tried to sell the things in the home to the guys frow still water, and because Teach was completely out, maybe his dad beat him to rob the house, he thought this gigantic guy is going to kill him, the last words are, "Look what i found. It's alright no need to be afraid. I'll make this a painless death... And Guwon killed him, and cut to him talk to Teach
Dude that’s a really good theory
No, I'll do you one further. That dude at the end is just a random burglar. The reason mc is subconsciously trying to kill ml could be linked to him killing his own father. Either ml reminds him of his father OR ml just happens to be near mc when he has these episodes and he could do it to anyone who is near him. Also he never mentioned having a brother. The father could, however, be the reason he had those bandages around he ankle and head. Chapter 3, mc is talking about his mom and dad and when ml asked more about his dad, his dad was wearing a different outfit than the dude that broke into his house. (But that could also just be the artist forgetting what they originally drew) anyways thats just my theory but i really do think mc killed his father after his mother died.
I think Jiwoo killed his father either before all of this happened or a little after the apocalypse started. I just reread chapter 0 and 1 and noticed that when Guwon first found mc after killing that looter, that he had picked up a photo of mc and his family. The glass on the fathers face was cracked so im thinking that indicates the type of relationship mc had with him. Im curious to see where this goes from here!!!!