This is an automatically translated description

Once upon a time, there was a vampire named Vanitas, and all the other vampires hated him because he was born under a blue full moon, not a crimson one. Frightened and alone, he created the Book of Vanitas, a cursed grimoire that will one day take revenge on all vampires... At least that's how the story goes.

A young adventurer, Noe, has heard about this book and wants to find it. He embarks on a journey to Paris by airship, because the trail of the grimoire is lost there. It seems that the book is really cursed, because in the city Noé is attacked by a vampire... But by some miracle, the young man finds himself closer to his goal, because the doctor who will take care of his wounds has heard of the grimoire, and moreover, his name is Vanitas.