Gu Jin was inexplicably obsessed with the girl in a portrait, but he didn't know the girl until he met Xiao Xia, a person whose appearance and name were ambiguous and male and female.
Knowing that Xiao Xia was the model, Gu Jin suffered from insomnia; knowing that Xiao Xia had someone he liked, Gu Jin suffered from insomnia; knowing that Xiao Xia liked someone other than a boy, Gu Jin suffered from insomnia again; knowing that Xiao Xia... Any news about Xiao Xia may cause Gu Jin to suffer from insomnia, and the most effective "sleeping pill" for Gu Jin is Xiao Xia herself.