This is in the Dragons Next Door setting, but NOT the narrator family or the Smiths. Elkin were going to be elf-kin, but I liked the typo better.
I think it's fair that I thought Farnah was male.
He was - pardon, zad was - the first elkin I'd had any real experience with, and he - zad - had, when naked, something that really looked like a penis. And functioned like one, as well, or at least close enough. Elkin are far enough from human that I didn't worry about babies (it takes magic, a stork, and the remnants of a dragon egg to make an elkin-human cross), so I didn't think, all that much, about the fact that zad didn't have testes. I always thought they looked silly on human males, anyway.
We had been together for several months when zad finally explained to me - after the age-old argument about toilet seats, no less, that zad was not male. Zad was hagadab, and, it turned out, the elkin have seven genders.
I, personally, sometimes thought two was more than enough, but I really, really liked Farnah, still do, and so I tried to learn more about my lover and zas gender.
They tend to be sloppy, I learned that first, but only in the nest. In the field, they are meticulous (I already knew this about Farnah. We worked, often, side-by-side, and spent most of our time in my apartment.) They like high spaces (the elkin are, after all, naturally alpine), and, it turns out, are the reason for the kendar myth. Already things I already knew about Farnah; shorter than me by half a foot, zad had picked the tallest chair in my apartment as zas and stacked pillows on it to make it taller.
The hardest part, as we adjusted to our cross-species romance, turned out in the end to be the easiest. The hagadab are the providers of the elkin family group; they hunt, they gather, they bring home Things. Zad didn't mind that I earned money, but me bringing home things made my poor Farnah bristle every time.
I never liked grocery shopping that much, anyway.