Evil Is Sexy: Ryo does work as a gigolo throughout the series and gets paid very well.
Moral Event Horizon: Ryo crosses this when he rapes Sugawara's girlfriend for the purpose of trying to set up a match between them, and to make matters worse, he calls Sugawara and makes him listen to her being raped.
Nightmare Fuel: Ryo tries to cremate Rangah on a funeral pyre after the latter apparently dies from injuries. Turns out he wasn't quite so dead.
This is taken even further for after the introductions of Sakiko. She and Ryo are meant to be Birds of a Feather given she has a crippling fear of her father. Her father is shown to be a loving and caring man who was willing to spend every dime had when he thought that Ryo had kidnapped her. Unfortunately, the people he hired turned out to be psychopaths. Yet Sakiko has an unexplained fear that he will kill her, to the point that she stabs him.
Also, for all her talk about wanting freedom she just latched on to the first person who likes her art. Making her come across more like an Entitled Bastard angry at her father for not understanding that True Art Is Incomprehensible