You know how when you're a kid there's that tempting box that you've heard bits and pieces about of what could be inside, but it's labelled as taboo to venture into it so that just makes you have the urge to look more just because it's labelled as otherwise?
Inside the box is a never-ending puzzle, it keeps you looking, trying different possibilities to see what makes the most sense in what can work, but it doesn't ever have a finished end, you can only make out partial images of something but then you're blocked.
That's how Columbine is to me, also applicable to some other true crime cases as well but mostly just ones with loose ends
On True Crime in general overall, I'd say morbid curiosity. You hear about something strange so you go to take a look out of curiosity and boom, you're now watching docus, videos, n reading stuff for an eternity
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lol that was funny