Love love love. And for me it doesn't have too much of a HP association. I loved it before those books. I first heard it on a movie character and it just clicked with me.
It could be a nn for
Virginia,
Eugenia,
Genevieve,
Ginevra (that would be too HP-ish), or
Imogen. My DH loves the nn
Ginny, too. We have
Virginia nn
Ginny on our list!