Obviously, Lucifer is dark; even though his name means "light bearer".
Lucifer's proselytes are dark as well.
Serial killers are Lucifer's proselytes.
They employ graphic, gruesome, violent methods to stalk and murder their prey. When the law finally catches up with them, they resign themselves to being caught. They know they're guilty and they don't care.
Many want to study the mind of a serial killer, like Richard Speck and others. Their rationale or reasoning is that if they could learn what is in the mind of a serial killer, perhaps they could profile and predict attitudes and behavior, and equipped with this knowledge, intended victims might be spared.
Naïve thinking, wouldn't you agree? Hey! Argue with the statistics.
Surmise is to infer with little evidence or GUESS!
Surmise is what one does because one refuses to go into the mind of a serial killer to try to figure out what makes them tick!
Perhaps some of them have real genuine stories about horrible childhoods, suffering abuse at the hands of their primary caretakers, etc. Perhaps these murderers are misunderstood, they've been hurting a long time, and it's a means of releasing rage and making others feel their pain.
But here is a salient fact and it is a contrast and comparison that anybody would be hard-pressed to ignore. There have been children who have endured unimaginable cruelties and they have grown up to become ... non-serial killers.