The entire house of vampires Victor visited first after his arrival in the vampire world had vanished as Victor made sure to kill every single one of them. He only left the one that led him there initially, as he was still useful in pointing the way to other vampires and their location.
At that moment after taking care of every vampire in that house of vampires, Victor was still a vampire noble, and since he hadn't eaten any of them, he wasn't sure if he had enough evolution materials to advance. Not that he thought he would, since the number of evolution materials needed for the next evolution into a vampire lord was really much. He was sure that more bodies would be needed.
As for eating the vampires and gaining the needed evolution materials, Victor felt it would be a tedious process to do all that, so he sought a monster or beast that would provide him the needed anatomical qualities to be able to swallow the bodies without much hassle or stress.
