Most of us already know that life isn't about rainbows and unicorns. Nope. You can fall to your death sliding down a rainbow. You can get gored by a unicorn having a bad day. Life can be very sad, ugly and violent. And these 15 crime-inspired songs capture the essence of some of the worst people in history. Spoiler alert: This is not a feel-good list by any means.

The tracks we've mentioned here aren't limited to one genre. That goes far to reveal the level of fascination people have for sadists and murderers. From preppy murderers to bloodthirsty monarchs to normal-looking serial killers, there's a lot to process regarding man's inhumanity to man. Wanting to convey that in song is another game altogether. We live in a climate where violence isn't real until it happens to you.  People who completely free themselves from societal standards will always be the subject of fascination and obsession. Having those things manifested in art is far better than walking that particular walk.

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Upon closer inspection, murderers and musicians have been doing the transgressive waltz together for awhile now. There's Charles Manson's connections to the Beach Boys and his intended record producer victim. There's a harsh noise artist named after someone namechecked on our list. What was the name of that side-project with members of AFI and Samhain? And let's not forget the artist whose band members' stage names were one-half pop culture icon and the other half killer.

So check out our rundown of crime-inspired songs. The influences come from a number of different genres and it's louder than a season of 48 Hours. You might want to leave the lights on while listening. Then again, what's that old saying? Oh, yeah: "With the lights out, it's less dangerous..."