As we are about to get into Dante's Inferno I would like to reference one of my favorite shows. Supernatural deals with hell frequently, especially throughout the first 4 seasons. Dean, one of the characters in the show, is sent there for making a deal with a demon by giving up his soul. When he comes back only about 4 earth months have passed, but in hell it has been about 40 years. The show plays around with the ideas of torture. There are no specificities about circles, but they do play with the idea that these pitiful souls are all humans, or well they once were. But they have been tortured so much that they have forgotten their human ways.