There's no doubt about it: she's godly. Here is another music video from teen singer Koeda, singing with supercell. The song, released in March with Kokuhaku, is called Our Footprints. The band appears on-screen starting about halfway through. Since this is from NicoNico, the embedded video will take a while to appear. Have faith.
Last summer, ryo held auditions to choose a new singer for supercell, to succeed nagi (Yanagi Nagi). He chose 17-year-old Chelly and 15-year-old Koeda. Their first work was OPs and EDs for the anime Guilty Crown.
Chelly was good, particularly singing the first OP/insert song Euterpe. But Koeda was...godly. I have never heard a singer with such power and musicality in her voice. For sheer vocal ability, Koeda compares for me with Onitsuka Chihiro. Ryo said that she was her own remix machine, singing the song several times and then choosing which approaches to use where in the final version.
I like the fact that in all of her music videos so far, the young singer's face is somewhat hidden. She's not ready for real fame, which is what will come when she makes her full public debut. From what we can see, she has a pretty face, to go along with her pudgy hands, and is a fairly big person. 2channel believes that all the music videos are really her -- and they seem to be the same person, at least -- but that hasn't been directly confirmed.
Koeda is on Twitter as @Chokoeda. She sounds like a 16-year-old high school freshman. Which she is, lol. There are no pictures of her face on Twitter, but we do see those pudgy hands.
Here is my previous post on Koeda. You can find quite a few of her own personal covers of other songs here. こゑだ神声だ