employee Kim Doyoon, a half vampire that needs sexual energy as his food source, acidentally sends a text to his directer Lee Kangwoo asking to be sex partners. Lee Kangwoo however wants a serious relationship with Doyoon, not understanding why he would want sex from him when he doesn't even like Kangwoo, so he refuses him sex. also for some reason Doyoon couldn't absorb any energy from their first time so he's getting frustrated.
K's secret