From what I can tell, Yuwon was the victim all along. In chapter 60, you can see his blurred memories where he is the one getting bullied, but he convinced himself it was Dohun.
The poem Dohun read during his childhood could also be a significant part of this. For him, “destiny” was the purpose of a being’s life. So when he met Yuwon for the first time, he knew that Yuwon was his “destiny.”
You can also notice that in the initial high school chapters, Dohun would come up to Yuwon while he was with his “friends” and tell them not to bully him. Now that wouldn’t really make sense since we never actually saw Yuwon getting bullied. Why? Because the story was told from Yuwon’s POV, and in his perspective, it was Dohun getting bullied.
Dohun saw Yuwon as his destiny, and his only purpose was to make Yuwon happy, so he manipulated and brainwashed his memories. Though I wouldn’t assume too much yet, since we’re finally getting Dohun’s POV.
Sorry it got long but there’s so many things i could pick up to think it’s actually Yuwon. Poor baby i wish he get happiness in future chapters

Wait, I'm confused?? So this whole time it was Yuwon who was bullied not the other way around?