According to Don Bluth's official Twitter page that Ichiei Ishibumi the writer and director of the High School DxD series died last year, All of the romanovs are dead. He died. Died died died. There's no confirmation about when is season 5 released but it will set in America and no longer in Japan. Also, Jamie Marchi (the voice of Rias Gremory) got fired from Funimation for threats of Violence and Scripts. So I decide to prefer Christina Kelly to voice Rias for this american Season 5.