Bones
This Creepily Beautiful Chapel in Czermna, Poland, Is Constructed Out of Thousands of Human Bones
When I visited Rome, I visited the crypt of the Capuchin monks. The monks used their order’s bones to create amazing patterns in a series of six rooms. It was creepy and yet fascinating. The motto that stuck in my head, which is listed on the Wikipedia page, is:
What you are now we used to be; what we are now you will be…
Now I’m reading up on the Paris catacombs. How did Hugo manage not to include these in Les Misérables somewhere?
Update: It would have tied in easily with the convent’s burial rituals or the sewers, especially since IIRC the sewer chapter also ties into the now-abandoned mines below Paris, part of which had already been repurposed as the ossuary before Jean Valjean’s release. Though I suppose the mines could have been brought up not in the book, but the podcast I listened to in 2018.