Ryuu holds the 7th position in school, although his test scores are a poor reflection of his intellectual prowess. He is in 7th place mainly because of the twins - Megumi tends to fall asleep and Jun becomes bored during the test, which results in Ryuu focusing the part of his attention on them instead of his own exam. He has been close to Megumi and Jun since they were very young; it is evident that he cares for the twins very much and that the three of them see each other as family. An even-tempered and kindhearted person, Ryuu loves animals and is good with children. He is also the first amongst the S.A to discover, by accident, Finn's true gender, a secret that few people in the world know, and appears to be developing feelings for her. He is the son of the CEO of a sports company and one of his family's clients is Yahiro's family.