It starts off as porn. I would quote a few reviews from the NU.
"I'm currently at chapter 800 and I can tell you this is good. It's well written with lots of actual plot instead of just pure s*x period lot's of dark societies, underground Mafia. Training and blackmail, correction, and all the good that is in the darkness of society."
"Like Pun, Cabman, and others have said the scale of this novel is huge. It was foreshadowed many times at the beginning, but it'll eventually explore the workings of Noble Families, Political World, and Yakuza of Japan. It's not a simple ero novel, it's actually a psychological novel."
And I wholly agree with those parts from the reviews. The story starts rather simplistic. It's hard to tear through all the rape things and similar stuff. However, eventually, it becomes very dark and attempts doing a heavy psychological plot. If it failed or not isn't up to me to decide. I liked the first part of the story quite a lot until a particular character appeared.