Halo

The terror this exudes and invokes a bit of in the viewer was the first thing that hit me here. The composition is great- difficult pose, dynamic without being too "actiony", and the way the lock of hair swirl down her is not only eye candy and good detail, but makes one think what this could be. The position of her hands, the look on her face, the way you did the eyes- all are fine details that bring the piece together. The ring is a bit crooked though, although I do like it- is she trapped or is this a planetary ring?, I ask myself- and the style the butterfly is draw in seems to clash with the way you did the rest of the piece.
I like the glow you gave the butterfly, too, although it seems that the ring ought to have some sort of light too, since otherwise there seems to be no other light source, so it makes me think that the girl should be in complete darkness.
Overall, this is a good piece, and definitely one ripe with "It could be this..." interpretations.