1. Mr. Yeon's Company has ownership in smaller companies. This is called a subsidiary.
2. The subsidiary was lending money/investing in MC's dad's company.
3. However MC's dad's business was failing. And he was making late payments for loans etc.
4. The subsidiary likely assessed that the losses were too great and no profit would be earned so they pull out their investment.
5. This would lead Mc's dad's company to need to seek out loans from shady loansharks to remain afloat. The business continued to fail and the dad probably racked up more debts trying to hold onto a sinking ship.
6. That's what the latest chapter reveals to us. So it isn't really Mr.Yeon's fault but rather his subsidiary pulling out caused a dominoe effect. The loans are on the dad for not making good decisions.
As someone above me said, the company that his family (?) owns, also runs another company that pulled out their financial help (or something like that) which fucked over his dads business and caused him have to take out loans and go into debt. So it doesn’t seem like he was directly involved but it was still their company. This is explained in the chapter of you wanted to go back and reread it
WHY DO I FEEL THAT THE REASON OF YEOMIN FATHER'S BUSINESS BANKRUPT IS MR. YEON FAULT OR HE'S INVOLVED? OOPSSSIEE, DID I JUST REVEALED THE PLOT TWIST?