Haibane Renmei inspired Uyraies (though there's already a bit about her inspired by Haibane. She looks so much like Reki, but that was really unintentional. x__x She came out that way before I even got into the series.)

For the curious, 'Haibane' is translated as 'charcoal feather', but I remember reading somewhere that 'ash grey feather' is a closer translation. I thought that the symbolism behind ash colored angel wings was so profound (ashes being a symbol of retribution, purification, rebirth, and mortality) that I wanted to adopt the principal with Uyraies. Especially since she already represents fire to begin with.

'Ailes Grises', by the by, is French for 'Grey Wings'.

This was a pencil and ink drawing with a bit of color added in on Photoshop.