This story is really violent (rape, blood,..) but that's not what bother me the most. I would say that it's a little repetitive.
I haven't finished the novel yet so I can be wrong but the fact that the MC is raped in all the Palaces... I really like the characters of the Twelve Beasts, they all have their weakness and soft point but, does the MC really has to be abused this way? The fact that he is raped isn't really the worst part, just... I don't know. MC being always raped and tortured and all and yet, he loves each beasts. I think it's kind the Stockholm syndrome but meh.