The Vampire Queen's Contract Story

Does Kyubey-kun's book need an introduction? Why did I transform into a vampire girl? … "Shut up, this is the supreme gift of the vampires! You should feel honored for this contract! The first step to conquer the world is to learn to suck blood gracefully!" "..." Book group number: 4.6.4.8.0.6.2.1.7 Children, you can add it