Chouji Suitengu's parents were murdered by the Tennozu Group when he was 12. He becomes an assassin in and aims to destroy the economy that devastated his and many other lives.
His background is a mystery. When the Tennozu Group was expanding on the corporate level, he was the lead player standing at the forefront, buying up corporations, and land, and is the reason the Tennozu Group stands as it does today.
Shinsen's trust in him is deep, and even now he works as Shinsen's right hand man, with all of the Tennozu Group's shadow work left to him. Because of this, he has never once been on center stage. In order to further his shadowy work uninterrupted, he established the Club, where the necessary political, government and economic movers gather together. He becomes the club's manager. Having secrets creates a feeling of togetherness, and the Tennozu Group's board becomes quite solid. That is the face that Shinsen knows, but there is actually a secret side to him that even Shinsen doesn't know about.
The Club's true purpose is to be a place where one can experience the ultimate pleasure. The ultimate pleasure is nothing less than to become the very object of one's fetish. In order to make this happen, Suitengu uses Shinsen's daughter, Kagura, and acts as the dark priest in secret, immoral rituals. That is his other side.
And this is how the super-beings known as the Euphorics are born. How he obtained that technology and what his goal might be is still a mystery. He is a man with mysterious ambitions.
No matter what time of year it is, he always wears a coat and gloves. He normally carries cigarettes made from money. He carries a small music box around with him, but it isn't because he's a romantic that he enjoys its tones. He owns several high-class cars. He changes what car drives depending on his mood. He lives for money, and works in service of money.
Cold and cruel, there is a deep darkness within his heart. Very little moves him, and he is normally indifferent. When he smiles, his eyes stay the same. He speaks as if he's giving a monologue, and there aren't many times when he raises his voice. His words are often sarcastic. It's hard to understand what he's thinking. He treats Shinsen and Kagura courteously, but is isn't like he is fawning over them.