Another point I'd like to make, I read a lot of people giving character references on the suspects of this case saying such and such would never hurt a fly, nicest person you'd ever meet, etc...
I don't rule out any nice gentle person. Did you see Dahmer on Dahmer: A serial killer speaks? I did and it scared the living sh## out of me. This guy was so kind and non threatening that the police officer who was with him after his arrest got neck massages from him. Said he never felt scared or threatened by him. A man who admitted to murdering multiple innocent strangers and his own mother.
Dahmer On Dahmer: A Serial Killer Speaks
So that's an example of a nice, gentle, kind, non threatening admitted serial killer.