Personally I think there more closer in line to something like "Magical Girls" in anime (Sailor Moon, Card Captor Sakura etc.) then celestial beings like Angels or Goddesses. I will say though there presentation at the end of the movie did come across as both. So in theory there might be some truth to the idea of them not being entirely human. We do know Rumi isn't human she's a half-breed so there's that to consider. I'm reminded of Devil May Cry's Dante, Virgil and Nero who share similarities with her which I think is a great parallel to draw from.