In manhwa, loving your enemy could mean learning their backstory and empathizing with their struggles. It also might require forgiving past wrongs and looking for the good in them. But it's not always easy!
The 'forced proximity' trope is common. Like being locked in a room together. Another is the 'redemption arc' where one of the characters changes for the better. And of course, the 'love - hate banter' which shows their initial animosity but also the underlying attraction.
There's also the 'external conflict' trope. There might be some outside forces, like family feuds or social differences, that contribute to their initial enmity. But as they overcome these external conflicts together, their relationship changes. For instance, in Romeo and Juliet, the family feud between the Montagues and Capulets is an external conflict that adds to their initial difficulties, but their love overcomes it in a tragic way.
One way is through shared experiences. For example, if they are forced to work together on a project. They start to see each other's strengths and weaknesses. Another way is by a sudden act of kindness. Maybe the 'enemy' saves the other from a dangerous situation. This can shatter the initial bad impression.
The 'lover boy manhwa side story' could potentially explore different aspects of the love interests in the main story. It might show some of their past experiences that shaped who they are in the main narrative. Maybe it delves deeper into their personalities and how they interact with the main character on a more personal level outside of the main events of the manhwa.
Lord Lamp was talking about a novel called " Family, Enemy, Lover ". This was a story about a younger brother and sister. The story was about the heroine who discovered that her mother had an affair with a strange man when she was young. She reported her mother's lover, causing her mother's reputation to be damaged. Her parents divorced, and her younger brother was taken away by her mother. When she became an adult, the heroine reunited with a young boy and began to fall in love. However, the female lead was involved in a major incident, causing her reputation to be damaged and she was suspended from her duties to pay compensation. In the end, the female lead revealed that she had always suspected that the boy was actually her younger brother and that he was here to take revenge on her.
Family, enemies, and lovers was a novel created by Lord Lamp. The content of the novel was mainly about the love and hatred between the sister and the brother. Her sister had doted on her brother since he was young, but when she was thirteen, she found out that her mother was having an affair with a strange man, and her brother was that man's son. The story began with the reunion of the two adults. They launched a series of tit-for-tat competitions and fell in love with each other. However, the specific plot and plot development needed to be read in full.
'Cruel Prince' by Holly Black also has elements of enemy to lover. Jude, a human girl, is in a world full of faeries who often treat her poorly. She and Cardan, a faerie prince, have a very antagonistic relationship at the start. But over time, their relationship becomes more complex and develops into a love story.