Not Going to Write It

Today I made a decision. I've been toying with the idea of whether or not there will be four or five more books in Perryville, Ohio and as of now I will only be writing three more. A new villain Dr. Nick Rugero-an undead, malicious forensic anthropologist will be introduced in the next upcoming book.
He was vaguely mentioned in the first interlude of Haunting on East 48th Street but he will serve as the main antagonist in books 3 and 4. I won't go into too much detail because we're not quite there yet.
The fifth book however was going to be kind of like his backstory. It would have featured how he became the undead entity that he was and how Detectives Banning and Ivory discovered him as the killer of a series of kidnapping/murders that they were investigating. More like a prequel to the first book.
As of now I decided not to write it because I don't want to ruin the mystery of this new upcoming villain by explaining too much about him. The main events are in the third and four book and it just doesn't get any better or scarier from there. I think explaining how he got there might downplay the fright factor of Dr. Rugero, but nothing is set in stone.
What does everybody think? Is a character more frightening when you don't know their backstory? Isn't it scarier to know that they slaughter and terrorize just because? Red Tooth has absolute no back story and I meant it that way. To give him one would absolutely kill the mystique. It's the worst thing I could do and I'm feeling the same way about Dr. Rugero.
However things change all the time so if you have any opinions feel free to share. I'll post another blog on the subject a little further down the road. Well thanks for tuning in everybody. Till next time.