Haven't got to the facial expression yet. Cant' get past the hair - light and texture are ... amazing. Oh - wait - there's her lips. Do you know someone that beautiful? Or do these women come strictly from your imagination?
I signed up on DevArt, just to be able to make this comment. This is probably one of the best pieces of art I have seen in my entire life. You Sir, have caught subspace perfectly, the subtle nuances in her face reflecting the mindset. It just jumped out right at me in sheer recognition, and for a few short seconds, I had a flashback. I was there. It does make my heart race faster, every time I look at it. Fascinating. Thank you.
Spontaneosly I would describe it as "the moment of surrender", when sub has the feeling he/she could let everything else go and devote oneself to one's masters/mistress' will. As a german native speaker I would use the saying: "when the knot bursts" - a moment of total relief...ironically xD.