"You're saying I'll be able to sleep once I drink your blood?" Kang Yiwoon is someone special who suddenly appears in front of Sul Hyunwoo who suffers from insomnia and lack of desire. Whenever Hyunwoo sucks the blood of Yiwoon, the human panacea, he will suddenly have a lot of "desires". Before Hyunwoo knows it, his sexual desire is also being managed by Yiwoon, but he says, "If you're here I become strange." A doctor and his patient sleeping together how far can the relationship between these two go?