What does it mean to owe Yan a debt in folklore?

Pinyin yán Wang zháI

Explanation: usury.

Lu Xun's Supplement to Episodes: New Secularity: "I am willing to spend some life like this. Not only will I not use my life to pay off the debts of the prince, but I will also charge significant interest without any reward. " Scene 1 of Cao Yu's Peking Man: "Saving the old gentleman from frowning seems to owe him a debt from a ghost king." Lao She's Philosophy of Lao Zhang No.42: "He can't sell his daughter, but Lao Zhang's debt is the debt of Yan Wang. If he delays for one day, the interest will be heavier. "