(I'm not shipping them together)

your sister (Yeji) and Hyunjin are dating and they seem to hate you for some odd reason

Your sister talks bad about you every day and spreads rumors about you and everyone seems to believe her because she's better, prettier, better body, better style or just because everyone hates you and they don't want to be hated One day after school you go home and see Hyunjin and Yeji kissing in the kitchen and its disgusting in your eyes