RSBM It's be interesting to know if there are actually more, or if the distribution of info about them is higher? Reading Whoever Fights Monsters, there was certainly no shortage of barbaric killers, however many of these things were simply local crimes that would not get national attention. This was indeed one reason to put together the FBI profiling team, so these cases would be handled in a consistent way nationwide. Anyway - interesting theory. I have no data on it! As for the rage - this one I have read about. Sexually motivated attackers often bottle/botch their first rape because they lose control in the initial assault and you see overkill. e.g Becky Watts I wouldn't be surprised if Chase raped summer after he "subdued" her - also common.