It's also worth saying that, like a lot of people might have done, I'd assumed the nurse was a woman when I started writing them, but then I decided I didn't want it to be that simple - this story was all about playing with presumptions - so I had her going on a date with Hannah, which means she's either a man or a lesbian, either of which is fine, but both of which challenge some people's societal norms which is something I think writers increasingly have almost got a responsibility to do.