Walt hold on.
Mom found out Iseul and Seonwoo has been fooling around, Iseul's brother has been crushing on Seonwoo for a while. Mom manipulated and arranged their marriage, Seonwoo got played so she accept. Iseul can't believe she got played and felt bertayed. <--- my theory.
I wanna kms now
Lol, this is just my theory. Most of the stories aren't published yet. But this is what I'm theorizing!!
i fear something happened regarding that "sell yourself" thing, perhaps the ex 'sold' herself to the brother to keep her safe or something. but idk