Yes apparently he was his stepbrother, and when the family had the accident Chang was the only one who survived. Since he wasn’t the nephew of the old lady she resented him. Edd resembles this stepbrother that’s why the grandma treated him kindly. Chang had feelings for Edd since way back, but he wouldn’t admit it. However he didn’t want to lose Edd so after Edd had the accident he payed for the surgery, used the debt as an excuse to bind Edd to him and began to act like an asshole.
They are not brothers or stepbrothers lol. Ed was just neighborhood. And Chang lost real, blood related family, his bro wasn't step brother.
SRY I WAS WRONG. The person above was right. Sorry.
So... liu is his brother or what? I'm confused about the relationship and the past can someone enlighten me :(