A 20 year old Stock trader and proffessor who is very smart and has a slightly aggressive attitude. His only friend in the world is Akira fudo and his assistant Psycho Jenny. he lives in a penthouse in Shibuya and studies Akira fudo daily for any changes in his body after being possessed by the Demon king Amon. He feels no emotions like sympathy or anger or happiness. Jenny does not speak at all and is mute, but dressed formally, has red hair. Ryo has a blonde bowl cut with blue eyes and often only wears white clothing.

Mute, is very observant and her appearance scares most people. She follows Ryo around most of the time as she is his personal assistant and secretary