Hye sung sure did left Byul at first but he was aware that Dojin would be a good father taking care of the baby, he was scared cause the baby wasn't planned but he never once emotionally abandoned byul once, he asked about the baby, thought about it and then came back and loved that baby like anything. On the other hand, Hye Sung's mother left him with an abusive father, only returned for divorce and not once she came to see if the baby is even alive with that good for nothing father. I don't understand people who trash Hye Sung, are they even reading the story to not know the difference.