I'm looking for a story I came across a year or so ago. The basic outline is that a guy wakes up in darkness and the system (I know, that's not helpful) and he is offered to select the domain of his Godhood. He chooses darkness and later chooses blood as a sub domain, I thank that made him the God of Vampires. Unfortunately, that search phrase is essentially useless because of a few other novels. He pretty quickly saves a woman that he turns into a sort of "minor" Goddess. His memory is messed up because of the system's interference, and he begins to slowly recall the memories of the previous God of Darkness. I think the title was something a bit cringy, but it never really matched the story. Thank you, for any help you offer. It's been driving me crazy for months.
It would be easier if that were the case, I hate edgelord nonsense and, as I said, the title didn't really match with the story's narrative.
Okay if you search using just the God Protagonist AND Vampires tags you get 8 results, the one that sounds closest to what you described is a novel called "I Became a Progenitor Vampire" although it is CN novel so I don't imagine it is what you were talking about.