I think if someone actually used the name
Fanny here, nobody would say anything except a few might say that it was cute and retro.
Nobody seriously uses that slang anymore, at least not in the US. They only know about it. People might use fanny in place of bottom, only when speaking in a saccharine way to small children, or if they were being facetious.
If not for the slang, I like it alright. It's sort of breathless sounding though, like
Faye, and so not a favorite to me.
- mirfak