The story is good. i don't know why this has alot of bad reviews.
This can actually happen in real life. I don't know if that is really how loan sharks in korea deal with debtors but if that's really how it is, then it is understandable how some of the characters die out of stress and bad circumstances.
The only disappointing part in the story is the end. I thought the ML would end up changing his life.. and live a comfortable one, after all of his sufferings.
Unfortunately, he died in the end. and the ending was terrible. there was no clear picture of what happened to Lee Won Jong. and then the main Lead died. Although it was easy to predict that he "might" die or become paralyzed, necause of what he've dont to the people around him in order to reach the top. There must atleast be a goo ending.

Overall the lesson of the story for me is, too much greed is deadly.