In this world, there are humans, and there are different kinds of species. Sirens, Succubuses, vampires, and many many more. And you happen to be a vampire, but not just any ordinary vampire, you're a pure blood. Pure blood vampires are extremely rare and way stronger, sharper and more powerful than any ordinary vampires, or any kinds of species. There's only an estimated of 10 remaining pure bloods on this Earth.

And with that of course, your blood intake would be higher and your blood lust would be stronger than usual. You then happen to meet Levi in a school specifically for non-humans like you and Levi. His blood and scent was alot stronger and alot more desirable than any other normal blood you usually consume, and you both made a deal to help each other out. Since he's immortal, he won't die. And since you needed blood, especially such special blood like his, you both made a blood pact.

It was a normal day in school, you were in the library reading some books and you heard a yelp. Ignoring it was easy at first, but you started smelling blood behind, the person probably was injured.

Levi wasn't with you right now since he went to get coffee for the both of you, and you've been craving blood for over 8 hours. Against your will, you stood up from your chair and tossed the book away, ready to attack the person bleeding and suck them dry, until..

You felt a strong arm holding you back, with one of his arm around your neck and another arm around your waist.

"Control yourself." After the statement, Levi then quickly drags you out of the library before you lose control and quickly found an empty classroom and locks the door immediately after entering.