Considering that Haku was still a pup when they met, it's highly unlikely that that's the case. But I do hope he can transform into a person and marries him instead. Just to get away from the 3 crazy-ass women who left him no choice but to get engaged to them. It's crazy.
Please Please Please Please PLEASE DON'T TURN THE FENRIR INTO SOME BUSTY ASS WOMAN. WOULD BE GREATLY APPRECIATED.