Jungkook married yn because he want revenge on her because he think that yn father killed his mother, jungkook forcefully married yn and now he will make her Life hell
Jungkook marries yn because he likes to dominate, punish and use her and he wants to satisfy his sadistic desires
Jungkook likes to see yn pain and enjoys her suffering and anguish, he feels that he owns her and have all rights to use her for his pleasure and for punishing her, jungkook use siya always for his own pleasure only