When Shouma was 23 years old, he proposed to Shibuya Miko on just the 5th time that they met and they married half a year later. He's a banker and the subordinate of the Maou of Earth, Bob, who is an international investor. He says while the Mazoku of Earth don't really want to conquer the world they pretty much control all of the world's finances. Bob chose him and his wife to be the parents of the next Maou of Shin Makoku.
His job caused him to move around quite a bit when he and his wife first got married which led to them getting into an argument when they had to move to New York that nearly ended in divorce and led to Shouri running away with Yuuri.
- (to Conrart Weller) "When you meet my wife and children you won't make that face! If you ever let them see you behaving like that, no matter how much you beg I will never let my child go to your world!"