Finally watched 1000 babies and I have questions

First episode gave me the creeps. And then it went downhill from there. Verupikkal dialogues, acting and a bunch of characters with no depth. I am left with 3 questions, if anyone can help explain 1. Babies can only be of a subset of parents’ blood groups. How did that match perfectly for all the 1000+ babies 2. So Bibin went psycho after knowing what happened, ok 👍 but then why not just kill everyone he wants without telling anybody about it. None would be the wiser. Why the cat and mouse game with the cops? I mean isn’t he supposed to be genius level smart? 3. So it wasn’t exactly 1000 babies but 1000 something babies. Is Bibin just a round number loving person and killing the extra few babies to make it 1000? I mean at this point I will take anything.