Ryuuji was a hunter from Hiroshima, who responded to Kurono's and Reika's call, to join the Tokyo team and fight against the invading aliens. He explicitly stated that he is not a fan of Reika and that the reason for joining the fight was because he supports their cause. Ryuuji seems to be more of a melee fighter according to chapter 338 though that may just be because he doesn't have a weapon. He also is an admitted virgin. He later dies, saving Kei from Eeva Gund. Dying with a smile on his face--saying that he has no regrets. He is soon revived and transfered back home, however, after Kurono and Kato defeat Gund.