Not sure

None of them because they all have at leat something that makes sense why they're all fucked up. None of them are really a mystery. You can't be crazy and not crazy at the same time. There's no reason to take life for no reason. That's ingrained in all life in some form or another, so to go against life's very purpose to exist means you're wired wrong, and so no, there's no real fascination it's all pretty text book

Jeffrey dahmer

Jack the ripper.