Probably not much different than any other animal fat soap (I know technically they have different properties, but for the most part lard, tallow, are good soaps, so you kwim) you just would need to know the SAP value of human fat to get the lye amounts correct.
I am sooo NOT a Brad Pitt fan. Literally the only thing I've liked him in was 12 Monkeys. - now granted, I haven't seen all of his movies, because I just don't like his acting, but out of the more than dozen or so I've seen him in, that is literally the only one I've liked.
The first movie I remember seeing him in, A River Runs Through It, is one of my all time favorites, but not because of him. I really like the story and have the book. At the time I remember thinking that he could really have been Robert Redford's son, they looked so much alike to me in that movie. Well as time goes by, their similarities seemed to disappear completely and only when I re-watch it do I see why I thought that at the time.
My brother lent me Fight Club after I started making soap. The mention of making soap was such a small part of the movie, I think I would have missed i if I wasn't watching for it. But of course, I never read the book. Maybe I will one day.