This behavior, if we are thinking JP-type killer, is not totally unlike OCD, but in a different form. It is triggered by a different need, but whoever has “normal” OCD, knows that it comes and goes. Distraction is probably the best form of dealing with it, and serial killers may stop killing when they are married. I think presence of another human being ties them up to reality. But left to own thoughts, they eventually come to the same impulses. MOO totally. I was interested in GRK, and he had a pattern with several long periods in between murders.