But where was the character development? DH just shifted the object of his obsession and delusion of ownership from Suha on to Siwoo. He never once showed any remorse or even acknowledgement of the horrible things he's done even after being victimized himself. He pulled the same kind of dirty tricks to get Siwoo that he did on Suha. Violence, threats, money, power abuse, nothing changed. He was the same start to finish. The only difference is now he's dealing with an adult and not a child, like Suha was when he first started abusing him.
i think what made the difference was the fact that he fell in love for the first time. And more than that he was able to become vulnerable. That didn't change when he started bottoming, it changed over time when he accepted what he truly wanted. So we get this idea of him being an emotionally immature person who was very starved of affection, we also see over time that he has morals and he is able to change, unlike his grey hair friend who was very devoid of ethics. He learned ways to show affection, how to let himself feel it back, learned how it feels to want someone and of course he was put through a bunch of shitty situations that kinda gave him a reality check. These all make up his character development. Now, I do agree with you that a Lot of stuff wasn't adressed, but with the way Doohyuk was shaped it would've made it possible to adress it properly. They didn't even adress his own rape and that happened recently... He had a lot of space for growth, which is why the ending is so frustrating.
The ending was so bad but not because they didn't end up together. We went through 30 chapters of some of the best character development written in bl just for them to go back tp square 1? The ending could've been so satisfying. Hopeful even. Maybe show a little bit abt redhairs past. More about siwoos commitment issues. They were great together and opposite what siwoo says THEY WERE IN SYNC. It's such a shame. This would've been a great stand alone story, where you didn't have the baggage that the characters carry from the og storyline. Its really such a shame.
Not to mention I've been reading this every tuesday since SUMMER. This manhwa got me through so much these past 3 months. I will really miss it. I wish to know why the author didn't give it the ending it deserves because they obviously know how to write well. Shame