Palace ladies in the Han Dynasty wore open-backed pants only for the convenience of the emperor (Emperor Han Ling). Emperor Han Ling is very lewd. He took a fancy to the harem beauty anytime and anywhere and dragged her to bed for sex. Different from later generations, the court women in the Han Dynasty wore open-backed pants, which sounded incredible, and they didn't wear anything inside, so they didn't even take off their clothes to facilitate the emperor's lucky.