Tan Merchant is a wealthy merchant and the father of Tan Tinglian. He deeply loved his wife and never took a concubine, as they were childhood sweethearts. After his son's death, he considered having another child with his wife but discovered she could not conceive. He trusted his son-in-law Shen Kuan initially, even allowing him to prepare medicinal cuisine for his daughter. Upon discovering Shen Kuan's plot, he violently attacked him with bowls and chopsticks and realized his son's death was likely also related to Shen Kuan. He was devastated to learn he too had been poisoned with infertility medicine. He aged considerably upon learning the truth about his son-in-law's vicious schemes, which had begun from the moment Shen Kuan entered the Tan household.
