That's very nicely put, invisible, and instead of repeating your words, I'd rather add my immediate thoughts to them (which is no critique, for overall I find this is a wonderful photo, and don't really feel as much competition between "angel" and door as others seem to do): I wondered instantly, within the first second of seeing this photo "Why is she wearing a black dress?" This is a genuine question, for I wouldn't think anything's random in your photography, paraddox!? If I may assume that your photos say more than just offer an image of a very good looking girl dressed up as angel, then there must be some reason why she's wearing a black dress. Is it up to us to decide? Is it open for any kind of interpretation?
Ah, another thought, one that was as immediate as the first, and one I had before I read the others' comments: that door looks like a church door. Not surprising that an "angel" might walk out of a church, but then this other question nags me: "Why is an angel clad in black?"