I don't remember the story correctly but I think it goes this way ....
The Japanese FL comes to Korea and the bad boy and a good boy fall for her then the bad boy falls for her friend and the FL is pregnant... so ... the good boy tells her he is willing to be the baby's dad(?)

"Those who stand at the top determine what's wrong and what's right! This very place is neutral ground! Justice will prevail, you say? But of course it will! Whoever wins this war becomes justice!"