None of these girls will live for very long, so some of the stuff like clit removal might be hard to bring in. There a several examples of slow loss of intelligence or a brain forced to work when it cannot, aka the brain has been turned into a pudding, then switched back on. All pain, no intellect there. I like the hippocampus part, he can do that without physically removing it too. Make her unable to understand why she is now being butchered, over and over. Fear center manipulation, I like, violent fever dreams that feel real, until she dies of a heart attack. Full intelligence drain of the bookworm is good too. Basically though I made this a crew of good people who are tortured just because.