Arkab
I'm not too sure about it...
Angel: 天使(てんし/tenshi)
Woman: 女の人(おんあのひと/onnanohito)
Female Angel: 女天使(おんあてんし/onnatenshi?)
面白いですね。
If there is an adjective for angelic, you could throw that in front of the word for woman.
If there is not, you can make the noun for angel and adjective by putting a 'no' at the end, which would translate to a rough 'lady of angel', 'Angel's lady', or the favored 'Angel lady.' Not too sure.
Because Tenshi is a noun, if I had to guess, I would say Tenshinoonnanohito would be acceptable, especially because no one on gaia will know anyway.
I think it will work, but I could very well be horribly wrong.