I have been to the trouble to look on lexicon, and I found Veela's in the book Fantastic Beasts and Where to Find Them. So apparently they are creatures and not really human at all, though maybe they are part human. *Shrugs*

Weird and farfetched concepts are always a good thing, they're hugely enjoyable. Whether or not they happen is a different matter but it would make the fact that you were the only one to say that, very satisfying.