The colors, the lining, it all really flows together. I love the flow of the hair and the posing is beautiful as well. A picture really does paint a thousand words, now if only I could explain those words. The butterfly is beautiful and you positioned it perfectly so the viewer knows it's not just placed upon her lips. Her eyes already seem like she's struggling yet giving up, which is an interesting addition. The fluids from her mouth drip very realistically as well. My only suggestion is to make the hand pop out from the neck a little more, whether that be with more shadow or darker lines, it's just a little hard at first glance to realize that's her hand. I had to look at it a moment to realize that wasn't part of her neck. Other than that, though, I have literally no complaints. It's a beautiful and moving piece and that's my favorite kind of art is one that invokes emotion. Well done!
I like the way you used the colours, really it's beautiful.