I was kinda wondering that because of BBtag,
he talked normal to her, but he was allergic to most of the other cat-like figures.
So what do you guys think?
Well, I believe since her cat like features aka her ears were under some clothes aka her bow. Hazama would not be able to smell he cat part to Blake
or
Maybe Cat Faunus like Blake dont give out the cat-like smell, that's why Hazama is not allergic to her
Those are just my guesses