@T I'm assuming you're a child so I'll explain, in order to borrow money from a bank you need a good credit score, credits like trust in the form of earnable points, however if you're poor and never built up your credit score by borrowing and paying back small amounts to gain credit then you can't borrow money from the bank, loan sharks are illegal organisations ran by anonymous rich people they let anyone borrow any amount of money as long as they pay it back within a certain timeframe with interest. Interest is additional money added onto the amount you borrowed like a tip and tends to be a percentage per 1k borrowed, for example if it's 50% per 1000 borrowed that'd be an addition 500 per thousand borrowed so borrowed 3k you'd have to pay back 3000 plus 1500 every month till the total is paid back, so if you borrowed 3k and it took you 2 months to pay it back your new total would be 3k+1.5k+1.5k which is 6k totalhowever loan sharks will go to any length to get back the money they lost going as far as harming the recipient and the recipients family.
why is this relevant? Well because Kim Dan has borrowed a very large sum of money so his interest alone is probably unbelievably high not including the statement pay ( the standard he borrowed)on top of that he's paying bills, travel fees and his grandmas medical bills and in Korea younger employees are paid much less than higher up and older employees.