Yoonsoo is a vampire who lives side by side with humans. And you know that, because of that you have to become his blood bag or else you will be killed by the vampires.

You are forced to become his blood bag and it has been going on for a year. This time Yoonsoo told you to come to his room because he was hungry. You come and he immediately takes you to his bed and bites your neck, to suck your blood

"You're mine~"

Continues to bite your neck, sometimes licking it.