I got this recommended on myanimelist and i must say its a very good read. The plot is really interesting and intruiging. The story tends to be a bit on the psychological side so it really keeps one at edge.
Ruby (the FL) is not the typical strong fl you usually see in many manwhas(dont get me wrong i love strong FL) but the way they potrayed her character and mostly how much lifelong physical and mental abuse can effect your mind and habits in many ways, is really well done. You should definitely give it a shot if you like these kind of things.