Wonho was definitely a complicated character. He really liked Min-ki, but took him for granted and was greedy for success. He didn't truly comprehend his faults until when Min-ki broke up with him for good. Because of his genuine regret afterwards, that was the start of his character redemption arc. So I couldn't help but feel bad for him with how much he pain he was in afterwards whereas Min-ki moved on from him pretty easily. But still, he deserves it, because he was abusive towards Min-ki for so many years.
Min-ki's guardian angel is Taeyoung, and they are truly lucky to have each other. I hope Eunwoo and Wonho's relationship dynamic will improve if there is a sequel, and they both become better people.
Wonho is a confusing character. I don't understand why he chose to sleep with sponsors that he didn't really like, if he liked Min-Ki so much. It was probably a mix of the entertinment business culture, his ambitions, and taking Min-ki for granted that led to his decisions. Perhaps something was also missing in his relationship with Min-ki that made him feel unsatisfied, something which he wasn't aware of.
In the end, it seemed they were not meant to be together. If there is ever a sequel to this series, I'd like to see how Wonho and Eunwoo's relationshi plays out.