It this story is accurate, there definitely was a "premeditation" involved here on his part.
Can't help but wonder if so, whether there were any "signs" of his demented, psycho, proclivities that others knew about, but ignored?
Thinking about your question, I recall that there is a standard comment made whenever a disgusting crime of this sort is uncovered:”He was such a nice guy. I can’t believe he did this. He was quiet, polite, funny and sensitive” etc, etc.
Perhaps there eventually are people who begin to speak out, a former girlfriend or wife or someone with an emotional investment who finally exits denial. However, psychopaths are usually bright and often very well-organized and capable of keeping these aspects of their lives separated.
this kind of depravity occurs around military bases, also wife swapping, all sorts of revolting behavior. Lifers in the military have no money problems, all their decisions including furniture for their quarters are made for them, all they have to do is live their lives. If they are stupid, this is the kind of stuff that goes on. If they have morals, they live a good life and raise their families.