Books where characters are being manipulated into changing/corrupted

I don’t know why I love this so much but I do.

I love stories about characters being broken down, and being put together again by someone without good intentions (bonus points if they where also the ones causing the breaking). Being manipulated to do the others bidding. Being corrupted to see the others flawed world view as right.

My favourite example of this is actually a fanfic but I am looking for books because fanfics with these themes tend to turn into smut and that is not what I’m looking for. (Plus many fanfics are quite badly written lets be honest)

I tagged this as sci-fi/fantasy because thats where I would expect to find it, but any genre is fine. It also doesn’t have to be the main focus of the book, but I am especially interested in the slow transformation and the psyche of the character being transformed, so I would want it to be more than just a few pages.

by tanglekelp