Why is dark history(dark subject matter and events) so fascinating?

For a little context I made a dnd character who is an archeologist who stands out for having a passion on learning and exploring dark events in history. I went through history podcasts and articles to learn things and I wont lie, just like in college, I was invested immediately. Learning about these people, events and tragedies.

Stuff I wouldnt learn in highschool like about unit 731 and how ,as bad as they did, help advance the field of medicine. Is it weird to think like this? Why is it so interesting to know things such as the creation of intricate torture methods or what led to mass killings either from a group or a individual?