An erotic film about the relationship between a man and a woman who met through sales of secondhand underwear. Sook-hee sometimes runs a high-paying part-time job, which is none other than secondhand underwear sales. One day, she meets with a buyer to sell underwear, and the buyer makes a big offer. That is, go to her house and buy underwear in bulk. After disposing of all of her underwear, Sook-hee introduces her part-time job to her younger sister, Hyang-gi, who lives with her.