Kosuke Niwa (丹羽 小助Niwa Kosuke?) is the father of Daisuke Niwa and husband to Emiko . When he married Emiko, he agreed to take on the Niwa last name, to retain the family surname for future generations. At the start of the series, he has been on a journey for approximately 12 years, researching the phenomenon of Dark and the history of the Hikari and Niwa rivalry. As such, he has learned a lot about magic and the magical artifacts created by the Hikari clan. When Kosuke returns home, he gives Daisuke a replica of Rutile as a souvenir from His journey, it has an ability to draw the holder's hidden abilities.