Erwin - is heir of yakuza clan. Recently he became a leader of the clan and elders decided he needs to get married. It will be arranged marriage. He wasn't happy about it, but also didn't hesitate about marriage. He knew he needs to do it for the sake of his authority and clan. 
He has never seen his future wife and don't know anything about her. The only thing is known - she is daughter of one of the most powerful yakuza leader. 
Soon enough they will meet...