They didn't even occur to her! She doesn't really think of them as vampires, probably because they're so different from the ones in her world. Angel still wins, but she would've said Yuuki to avoid the awkward.
IN WHAT CAPACITY hmm. Kanda feels a little weird about all the modern women he's met, he's used to being -- slightly less rude to women than to men, and he's never done so much flustered shouting at them before. So when Kanda thinks of Kitty, he gets derailed by things like that tag you gave me where she said this was no time to be flirting with her and Kanda has no response to that except for the part where his head explodes.