He researched it during this time. That blood serves him to create new existences; honestly, he doesn't need a body to do it. Making the body will take some time and resources.
But what would happen if he used this on an existing person?
What would happen is that he would not need to suck your blood to turn you into a vampire (in case you are of other races). This would improve the bloodline, body, and so on, although certain minor requirements must be met to do so.
Thanks to that, the versatility he has gained when it comes to 'creating' vampires allows him to better understand who he is.
A Vampire Progenitor, the one who started the race or who inherits the power that started it. His status is incomparable no matter how much he thinks about it. Even though he already knew it, every time he used his powers to that end, he realized that his life had truly changed and that his status, though towering, could not be openly revealed.
