Just a short little AU that sprung to mind. What if the book really had bestowed insane power on the reader? As usual, I owe nothing but the twisted little plot bunny.

Erin's blood drenched the book and the last words appeared on its pages. Bertrand threw her to the floor and began to read, feeling all the power he'd carried the key to for centuries flow through him. He closed his eyes and summoned the Dracula children to his side with no more than a thought.

"Bertrand, what-? How- Erin!" Vlad dropped to his knees at the slayer's side, shaking her lifeless body.
Ingrid, meanwhile, glanced from the girl to the Book and then back up at Bertrand.
"Bertrand. You've never been so sexy." He ignored her; she was just here as a witness.
"Yes, Vlad, I killed your little breather girlfriend. And now I have ultimate power over you all. I can't be slain, unless someone is foolish enough to try to drain me and lucky enough to succeed. This could have been your power, and now it's mine, just because you couldn't accept that she had to die." He crouched in front of his former student, fangs bared, mocking him. "Doesn't it make you angry?"

Vlad stared at the corpse that had been his girlfriend for a few more moments before his head snapped up.
"Yes."
The word was delivered with all the force and power he had ever been able to command, and it was all the warning Bertrand got before Vlad tackled him to the ground, sinking his fangs into his neck as he continued speaking directly into his former tutor's mind.
You shouldn't have hurt her. I told you what would happen if you betrayed me again. He could feel the power coursing into him from Bertrand's veins, even as the vampire beneath him began to flake into ash.

Bertrand lay still and unresisting.
Be great, Vladimir Dracula. He closed his eyes as he crumbled. I did it for you.