The role of villain is significant in K-dramas. Having a antagonist character, the story can have a nice flow well. Some villains in dramas can get much attention from the viewers. Their great acting and nice role can make viewers love them more.
Reported by Soompi, the first villain who got much attention was Lee Jae Wook in "Blood." He played protagonist role in this drama. But towards the end of the drama, the reasons for his action were revealed and he got much sympathy from the viewers.